(*See my update at the bottom of this article)
In his highly inflammatory post, Challies utilizes zero Scripture to support his case and through analogy with the secular world accuses watchblogs or discernment blogs as utilizing evil as entertainment, merely because such watchblogs act as watchmen in portraying the errors within the professing visible Church. The irony that Challies is, in this one post of his, doing exactly what he accuses the watchblogs as doing (portraying the errors within the professing visible Church) is seemingly lost on him as it has been written:
Take note of the irony here: what we just read was a blogger concerned about watchbloggers watchblogging, issuing a very pointed criticism against watchbloggers in general, but in point of fact was watchblogging about other watchbloggers on his own blog. 
Whether rightly or wrongly, criticism comes to all of us, and to attack the act of discernment and discernment ministries themselves because criticism occurs is utterly fallacious. In fact, since Challies is discerning the watchblogs here, why isn't this act of his done in the flesh?
The second links to New Evangelical Frank Turk's article that discernment is to be exercised within the local church. Since discernment ministries are meant to inform people of error and in so doing contributing to the Great Commission by warning the flock of possible soul-destroying error, Turk's peculiar ecclesia localis centrism logically leads to the conclusion that evangelism is to be done only within the Local Church! This is simply untenable, and therefore Turk's view of the Local Church is in error.
Last of all, it will suffice that Turk is violating his own advice since this article of his is not posted within the context of the Local Church anyway, not to mention Turk is not a pastor or elder so he has disqualified himself on his own principles!
Challies finished by basically repeating the essence of his initial post. In his own words:
But a blog that has as its bread and butter exposing error in the church, and especially error that is completely decontextualized and irrelevant to any of its readers, is a blog I think we ought to avoid. A Christian’s thoughts ought to be dominated by “whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things” (Philippians 4:8). As I said last Monday, “Do I really need to read and to know about the seedy underbelly of the church, when such things happen thousands of miles away, among people I will never meet and in places I will never be? Such news is plenty entertaining, but it is useless to me. It does nothing to further my faith or to cause me to grow in godliness.”
How does Challies know whether a person is operating a watchblog because he is concerned over others, or because he wants to destroy others or entertain others with evil? He doesn't! Also, we shouldn't confuse the motives of the writers with the motives of the readers. If people read it because they want to be entertained by evil, the blame should be placed on the reader not the sharer of information, unless it can be proven that that was the motive of the sharer in posting it also.
Challies with his view of being loving and positivity has manifests his New Evangelical convictions and Challies with his view of being loving and positivity has manifests his New Evangelical convictions and has done damage to the cause of Christ, with legitimate discernment ministries de-legitimized and the enemies of the Truth emboldened....
End quote. For the full context please go here: Source. (emphasis, mine)
Discernment is seen as a negative gift and therefore is one of the most unwanted and unwelcomed gifts from God by those who claim Christ. Why would a Christ-follower reject God's gift?
Discernment is judged by self-proclaimed non-judgmentalists as judgmental.
Discernment is seen as unloving, but it is precisely because of God's agape that He has gifted some of His children and therefore churches, with it. It is for their protection, as the Great Shepherd of the Sheep should be doing. Likewise a true Undershepherd as well, should appreciate and utilize the Discernment gifts to help aid in the protection of his flock. (You ought to see the persecution of those who have this gift--most wouldn't be able to stand up under such furious fight from "christians"--we're the first to feel the rejection).
People who have a distain for discernment like to determine how the discernment is to operate. These people don’t have the gift themselves, but they sure want to decide how and when and with whom and what it will be used for. Isn’t that hypocritical? Discernment naysayers desire to dictated and control those with the gift, and we know what that means: SHUT UP and SHUT DOWN the gift. It is the height of pride to neglect and reject discernment, for it is a spiritual gift God gives to protect His children and to honor His Word.
Challies, Turk, and their defenders should read what GOD Says about the gifts HE gives:
1Co 12:5 and there are varieties of service, but the same Lord;
1Co 12:6 and there are varieties of activities, but it is the same God who empowers them all in everyone.
1Co 12:7 To each is given the manifestation of the Spirit for the common good.
1Co 12:11 All these are empowered by one and the same Spirit, who apportions to each one individually as he wills.
1Co 12:17 If the whole body were an eye, where would be the sense of hearing? If the whole body were an ear, where would be the sense of smell?
1Co 12:18 But as it is, God arranged the members in the body, each one of them, as he chose.
1Co 12:21 The eye cannot say to the hand, "I have no need of you," nor again the head to the feet, "I have no need of you."
1Co 12:22 On the contrary, the parts of the body that seem to be weaker are indispensable,
1Co 12:23 and on those parts of the body that we think less honorable we bestow the greater honor, and our unpresentable parts are treated with greater modesty,
1Co 12:24 which our more presentable parts do not require. But God has so composed the body, giving greater honor to the part that lacked it,
1Co 12:25 that there may be no division in the body, but that the members may have the same care for one another.
1Co 12:26 If one member suffers, all suffer together; if one member is honored, all rejoice together.
The Discernment Naysayers ARE saying "I have no need of you", when GOD says, "Oh yes you do!". Why do they quarrel with their Maker? And where is the reverence of the Sovereignty of God they say they hold to?
I find it interesting that Challies denies the right, even the necessity of being “negative” for everyone but himself. This is hypocrisy. Apparently only he can determine what is useful for folks and what is not. Now, why is he the determiner of these things? Could it be that he thinks higher of himself and his influence than he ought? I say yes he does.
Rejecting God’s discernment gift is one of the reasons so many people have been captivated by Rick Warren, Mark Driscoll, Paul Tripp, the Emergent Church Movement, the Seeker/Pagan Friendly movement, Eastern Mysticism, Contemplative prayers, prayer labyrinths, etc.
While Challies makes a sweeping smear of Discernment sites that actually help others obey Scripture, he himself embraces the very evil we seek to caution others about.
Challies has applauded Donald Whitney and his book on “Spiritual Disciplines”. While Challies questioned the use of Richard Foster (a New Ager), he managed to swallow the pill despite the poison and then write highly of it. In other words, Challies finds a lot he likes in the book (calling certain actions "spiritual disciplines" even if its not biblically supported, or moreover, promotes a false teacher like Foster), yet he finds little use for Discernment websites that caution against such error as New Ageism, Romanism, carnality, etc?
I wonder if these Discernment Naysayers would slam Paul, John the Baptist, John, Jesus, Jude, or Peter for being so negative? Are we not to follow their example as they followed Christ’s?
2 Tim. 2: 16 Avoid godless chatter, because those who indulge in it will become more and more ungodly. 2Tim 2: 17 Their teaching will spread like gangrene. Among them are Hymenaeus and Philetus, 18 who have wandered away from the truth. They say that the resurrection has already taken place, and they destroy the faith of some.
2Tim. 4: 14 Alexander the metalworker did me a great deal of harm. The Lord will repay him for what he has done. 15 You too should be on your guard against him, because he strongly opposed our message.
3 John 9 I wrote to the church, but Diotrephes, who loves to be first,will have nothing to do with us. 10 So if I come, I will call attention to what he is doing, gossiping maliciously about us. Not satisfied with that, he refuses to welcome the brothers. He also stops those who want to do so and puts them out of the church. 3John 11 Dear friend, do not imitate what is evil but what is good.
In essence, Challies is decrying what these men wrote. And it should be clear: these letters were circulated to multiple churches. In addition they became even more public as they were Scripture!
See the Sacred Sandwich for more examples of how today’s “evangelical Christians” Discernment Naysayers would take on the apostles or Christ Himself.
So what it comes down to is this: positive = godly, negative = fleshly. Who decided this and how do they define these things, given the "negative" statements made about specific people in Scripture? Or is it ok only if the person is dead? Do we have a new secret standard God to only a few?
Those whom God has gifted with discernment often are looked upon as a bother, a thorn in the side of many. The gift of discernment doesn't fit into the Post-Modern thinking in today's "evangelical" circles.
As Spurgeon said in "A Reply To Our Critics" in "The Downgrade Controversy":
We are grateful to the editor of Word and Work for speaking out so plainly. He says:—
"In The Sword and the Trowel for the present month Mr. Spurgeon gives no uncertain sound concerning departures from the faith. His exposure of the dishonesty which, under the cover of orthodoxy, assails the very foundations of faith is opportune in the interests of truth. No doubt, like a faithful prophet in like evil times, he will be called a 'troubler of Israel,' and already we have noticed he has been spoken of as a pessimist; but any such attempts to lessen the weight of his testimony are only certain to make it more effective. When a strong sense of duty prompts public speech it will be no easy task to silence it.
"The preachers of false doctrine dislike nothing more than the premature detection of their doings. Only give them time enough to prepare men's minds for the reception of their 'new views,' and they are confident of success. They have had too much time already, and any who refuse to speak out now must be held to be 'partakers of their evil deeds.' As Mr. Spurgeon says, 'A little plain-speaking would do a world of good just now. These gentlemen desire to be let alone. They want no noise raised. Of course thieves hate watch-dogs, and love darkness. It is time that somebody should spring his rattle, and call attention to the way in which God is being robbed of his glory and man of his hope.'
2Jo 1:9 Everyone who goes on ahead and does not abide in the teaching of Christ, does not have God. Whoever abides in the teaching has both the Father and the Son. 10 If anyone comes to you and does not bring this teaching, do not receive him into your house or give him any greeting, 11 for whoever greets him takes part in his wicked works.
Daniel Chew once again deals with Challie's continued attacks on discernment bloggers. He says in part:
"Regardless, the main issue is that Tim Challies has decided that the best way to take revenge against the person who wronged him, is to condemn "discernment ministries" without distinction or exception, and smear them with the same broad brush as being essentially Pharisees...."