First and foremost, it’s the community. From the founders on down it’s quite a smart bunch, which I really appreciate. More importantly… from the founders on down, they care. The rules (and enforcement of them – GO MODS!) about how to ask and answer questions keep the site easily understandable (spelling and grammar are big here, and no txtspk) as well as friendly most times (no personal attacks). Those same rules tend to drive some people away, but it seems like the cream of the crop usually find a home here (which brings us right back to the community). The two things really feed each other.
On to the likes/dislikes:
I love the design. Crisp, clean, and a little cute, but not overly so. I love the hidden and not so hidden humor built in. Easy to navigate. I like that there is lurve, and that it has no actual value. I like the ‘learning’ matching algorithm that sends specific questions to specific users.
I’m with @Dog and @johnpowell on the idea of an area for general chatter (other than the chatroom). If there’s one thing I miss about my pre-mod days, it’s the chatty threads we had every once in a while. I’d like to see them return, but not on the front page.