Many have already taken Donald Miller to task for his express marginalization of what he labels as the "traditional" way of "finding intimacy" with God through the church.
Perhaps one critical aspect of Miller's "personal preference" that has not yet been addressed is its relationship to the so-called unpardonable sin. Thomas Goodwin, in The Trial of a Christian's Growth has this to say on the matter:
"Or else, as was said, they of their own accord 'forsake the assembly of the saints.’ The Apostle makes this a step to the sin against the Holy Ghost, Heb. x. 25. He saith, that when men forsake the assemblies and company of the people of God, public and private, and love not to quicken and stir up one another, or begin to be shy of those they once accompanied, they are in a nigh degree to that which follows in the next verse, 'to sin wilfully after they have received the knowledge of the truth.’...And if any soul begin to forsake the assemblies of the saints, or be cast out from them, let him look to himself lest he wither in the end, and be twice dead, and so he never come to have life put into him again; that is, repent and return again. And know this, that if you, being, cast out by the church and people of God, break your hearts, so that you mourn for your sin, as the incestuous Corinthian did, it is a sign you are such branches as God will yet make fruitful; but if, being cast out, you begin to wither, as here, the end will be burning." (emphasis mine)
Imagine a hand saying to the rest of the body, "I don't find satisfaction in being attached. You, arm, you're such a bore. All of you, you stifle me! I want to be free." Detached from the arm and the rest of the body, this "postmodern" hand, cut off from the nourishment of a consistent blood supply, soon decays and dies—nothing fit for it then but to be thrown into the fire.