Fun fact: two different times (so like half of the time) I've seen NeoGAF get trashed on /v/, I've randomly seen someone compliment me specifically as "one of the good ones" when that topic comes up. It's very flattering and kind of weird. I'm assuming it's someone who already posts on this board.
I was actually drawn back to /v/ only recently with the recent mod drama that linked into what would become "GamerGate" (a friend of mine browses it and told me about it). I actually used to post/browse on /v/ a lot during my FFXI days (that game is perfect for multi-tasking for better or worse). All in all, it was pretty terrible by most metrics (especially since there are few things I dislike more than people bitching and whining about videogames, especially for secondary out-of-game reasons) and only got worse and worse and worse. It undeniably better today than when I stopped browsing it completely.
It's weird knowing that I've seen the rise of memes (I generally disliked) like ">implying", brofist, the green frog comics totally changing in meaning, face images being ripped right out of various mspaint comics to also change in meaning, fucking dubs - dubs actually made me quit 4chan (well, it was the final straw). At one point, literally ever thread was "dubs" and I just decided since I never really liked posting there in the first place (although arguing is as addicting as always) I really need to stop going there (plus to avoid spoilers). Anyway... it just a little weird seeing these jokes all around the internet and thinking "I was, like, standing there x number of years ago when that became a thing - and I thought it was stupid as fuck".
The most tragic board was /co/. I'm not sure what it is like now, but following it from its inception, in short order it went from a legit comic board with some cartoons to 90% about cartoons to just the most vile fetish stuff and shitty artists pandering to deviant losers with said fetishes (and this was before My Little Pony really hit it big, I can't fathom what that was like). Getting pissed just thinking about it. It had more loli and waifu content than /a/. I've had always blindly hated /a/ for reasons like that, but now it is my favorite board (in fact the only board I really visit or bother to post in). Threads about particular manga are great. I read Bleach just for /a/; the esoteric humor that comes from dealing with Kubo's nonsense is just wonderful. I also really like their regular One Piece, (manga) JoJo, Hunter x Hunter threads (along with Berserk, Legend of the Galactic Heroes, etc., any stuff I like).
I've never really posted or looked at /b/ nor felt the need to. /v/ became /b/ only a few months after I joined anyway.
To close off my rambling, the "catalog" is probably the most amazing feature they added after my time. It completely changes the dynamic (although I imagine this detracts from the classic 4chan experience, as terrible as it was). I probably wouldn't bother without it.
EDIT: Something that I pissed me off at the time, which I'm reminded of whenever I see it today: Whenever people post 4chan screencaps, there's always that useless reply that adds nothing. For example, that popular (but terrible) Miyamoto-Zelda one, I think there's a reply that says "He's right!". This is, no doubt, that's the guy who took the picture in the first place and wanted to immortalize his anonymous self.