Somewhere, maybe here, someone used the example of Something Awful as what might eventually happen to FA. The long and short of it was that SA pretty much couldn't sustain itself with the amount of work required to keep it running, and no one was ponying up donations and Lowtax or whoever didn't feel like subsidizing the user base. So they started charging for access to the forums, and minimized the loss of existing users by grandfathering accounts. It didn't work well, but it apparently generated enough income to sustain the site. Or something. I don't remember exactly.
And it's all bullshit. They double dip with ad revenue and revenue from accounts/avatars/whatnot. Especially when you consider they have a fairly crappy frontpage and just a modified forum software holding the majority of the site together. Oh, and don't even start with volume of traffic or bandwidth excuses. 4chan is doing just fine with pretty much the same ads. Dammit J-list, I don't even want a friend in Japan!
As for FA, the way the fandom usually works is any 'community' site is little more than an ego operation for the handful of people running it. Unless it's not a furry site originally, like livejournal. Things get replaced, like how FA replaced Sheezyart. Maybe eventually FA will go away, or kick on as a living dinosaur like so many before it, but he'll try anything socially 'safe' first to avoid that. I kind of agree with Conan, he's willing to pay to cart 2's useless ass out to FA:U for no other reason than to have all the bells and whistles for his own little shin-dig.
FA is simply put, the biggest internet phenomena the furry fandom has ever gotten into that was a home brew. Sure, it's a clone of a clone of Deviantart with about 10% of the functionality, and in large part the popularity is due to the snowball effect of everything from the Furnation era passing away and the influx of kids who identify as furry like it's a culture/fashion fad a-la 'emo', but it's not going away anytime soon. It has it's own con for fuck's sake. VCL never could claim that. The cub porn hubbub was over lawsuit potential, not them failing to meet the bills. If anything, failing to meet the bills would be mismanagement and ad related more than anything.
The real problem with FA, the thing that WILL eventually be the linchpin of it's own mortality, is that it offers very little in the way of service. At least it offers virtually nothing someone else can't do, if not do better (and for a while that was the Inkbunny pitch). What it offers is the people who are there. The come because so-and-so is over there. Which also means in theory when the numbers thin, it will domino into an exodus.
It really is funny to think of the entirety of the fandom as a band of nomads, with an unrelated landowner declaring himself king when the tents go up and then retiring with a bitter cadre when the last caravan pulls away, over and over again.