To treat it fairly as I can, and to give it as fair a reading as possible, I would say that it really isn't that different from what Fr Dwight Longenecker, or Monsignor Charles Pope, is proposing. Oh, I grant that the subtitle ("A Catholic's Case for Gay Marriage") is a bit misleading on that score , since he really doesn't make a case "for" so-called "gay marriage." Instead, he makes the case that we should all stop fighting it, at least in the civil sphere. Granted, he uses more than a few grating lines in his tedious tale; I especially groaned when I read this one: "Just as there’s a rule in some online discussion groups that you’ve automatically lost an argument if you compare your opponents to the Nazis, so there ought to be a rule in public discourse that you’ve guaranteed your failure if you compare modern America to the decline of Ancient Rome." It's possible that people are weary of hearing about this, but that does not make it any less true.
Anyhow, that a conservative Catholic is calling for the Church to change her approach to the whole "gay marriage" issue is nothing new. Monsignor Charles Pope has argued before (twice) that we should consider divorcing civil marriage from Holy Matrimony, with the Church then getting out of the civil marriage business entirely. Father Dwight Longenecker has more recently suggested something similar. I still think that these two priests are wrong, but I notice that neither one really elicited the same kind of reactions (both for and against) as Jody Bottum, at least not immediately and not in quite the same volume. And, much as it makes it into every other (negative) appraisal of Mr Bottum's essay, I suspect this has nothing to do with the medium chosen to present the argument  nor the source of (financial) inspiration behind the essay, though these didn't help.
Rather, I suspect that the crucial difference is that the posts by Monsignor Pope and Fr Longenecker read like proactive though apparently passive resistance to the march of "progress," whereas Mr Bottum's essay read more like a preemptive surrender. In part this may have been the focus of each essay: the good priests focused on the distinction between Holy Matrimony (the sacrament) and marriage (the civil institution), and on how the Church would refocus on and fight for the former in the face of losing the fight on the latter. Contrast this with Mr Bottum's essay, which devoted roughly 1500 words to his gay former friend  and managed to sound more-or-less like the Church's position against "gay marriage" was hurting more people than it helps. In reality, the Church's stance against "gay marriage" is motivated by metaphysics and morality rather than by bigotry, but from reading Mr Bottum's essay you would almost come to the opposite conclusion . Thus, in the words of Mark Shea, Mr Bottum is "God's good servant, but the king's first":
If he wants to say, “Most Americans oppose the Church on this and realism dictates facing that fact” he gets no argument from me. But he’s saying, “The Church needs to get with the program and pretend gay ‘marriage’ is something other than a fantasy agreed upon by a culture that is radically out of touch with reality.” His core message is “Surrender”, not “Maintain the Tradition in a hostile culture.”It is certainly easy to read Mr Bottum's essay in this way. And, in fact, I have read little to suggest that he intends anything other than surrender by his writing. Sure, he has this short line:
if that’s what the same-sex marriage movement is really about—the redefinition of history as Christian oppression, the rereading of even success stories like the civil-rights movement as tales of defeating Christian evil, all for the purpose of cutting off the religious roots of Western civilization—then to hell with it.But this is precisely what the "gay rights" campaign is turning into. Add to this the timing--had he written this essay 10 years earlier, minus the parts about the culture's shifting attitudes, it might have looked more prophetic, more "be careful which battle you choose, and how you choose to fight it." It still has the quality of a warning about choosing carefully the beach or hill on which to die in the culture war, but it lacks that sense of doing so for the actual good of the Church as delivered. It looks far more like a tired missive explaining why he will be AWOL from this particular front of the culture war from now on--and why the rest of us should give up, as well. There are no hopeless battles when one fights on the side of the Church, even if victory in the here and now is far from assured, and even if not all the victors survive.
To hell with it, as well, if the campaign for same-sex marriage has anti-Catholicism as one of its major causes, or a feeding of anti-Catholicism as one of its welcome effects.
But to return one last time to the two priests, I note that their concerns really do seem to be more about how to "Maintain the Tradition in a hostile culture," inasmuch as they suggest something for the Church to do other than to surrender. Theirs is still a withdrawal, but it is a withdrawal to rest and regain strength, to renew the Church and then from there to renew the culture. For all of Bottum's musings about wanting to "enchant" the culture, I see no coherent plan for doing this. He may be saying essentially the same thing as Monsignor Pope and Fr Longenecker, but with one crucial difference. Whereas Monsignor Pope and Fr Longenecker's posts convey a sense of renewal and hope beneath the pessimism, Mr Joseph Bottum mostly conveys a sense of weariness and despair.
 Of course, there is no such thing as a Catholic case for "gay marriage," but I suppose that Catholics can at times break with the Church, at least on prudential matters. This doesn't make that break right, however.
 For the priests, it's personal blogs as opposed to the somewhat liberal Commonweal for Joseph Bottom. It is that same Commonweal in which we also read something of praise for the New Mexico Supreme Court's decision against a photographer who refused (on grounds of religion, conscience, and freedom of speech/association) to photograph a gay commitment ceremony and was promptly sued by the homosexualists involved. So much for tolerance from the homosexualists, which in this case includes the gays in question and there defenders at Commonweal.
 And rather pointlessly, since he concludes that his about-face on civil marriage is "not the answer same-sex marriage advocates want" and, showing that he really does understand that his surrender probably accomplishes nothing, he continues with "Certainly it will not satisfy Jim Watson, my old [gay] friend from New York. How could he accept talk of the Catholic Church’s charity and evangelizing? He wants the church hurt, its tax exemptions and even property-holding rights stripped away until it not only accepts laws allowing same-sex marriage, not only encourages same-sex marriage, but actually performs same-sex marriage."
 Yes, I know that he devotes some time to the idea of "enchanted" metaphysics and "enchanted" morals etc, and that his stated purpose is the work to the re-enchantment of the culture. But much of the rest of his essay sets up to paint the fight against legal recognition of "gay marriage" in a bad light, as if it is a bad fight.