I know a lot of furries who left their own sites, sites they built, to post exclusivley to FA. I don't think it has to do with lack of competition. I don't think furries ever cared at all for competition. These are the same people who can buy Pocky by the truckfull without ver realizing it's Japanese. Mob mentality, and high school fads plague this group. And in that sense, is why people prefer FA. It has everyone they know, they can watch, favorite, and 'befriend' people with a click of a button, just like dA, they can top that all off with comments that usually consist of either "you draw good" or "this is hot/sexy/funny/deep", and yeah, it fits their social networking. It's an online con. They brush by each other, unload their wallets for comissions, giggle, swap smut and bumble along.
Really, without the feedback, the site never sould have taken off. I've already heard a few angerly complaining that on specific forums, they don't get the kind of responses they'd like. "I have 10 views but no posts WAAAA". It doesn't matter if say, unlike dA there is never any constructive criticism, they just want fellatio for having actually put 5 minutes of their time into some drawing of tits or story about inflation.
I'm curious to see how reactions will change when the search function returns.