Like being involved in a gaming community. There are people I know who game, but not to the same extent - they don't know, and would have no interest in, games outside what they already know, with very few exceptions. And none have any interest in stuff like sales.
Also like the size of this site. It is small enough that you get to recognize people after a short amount of time, easy to remember what they are generally about, but it is big enough to generally be busy and have a decent amount of things going on. I would probably be on gaf too if their sign up policy wasn't what it was, but I would still come back here anyway.