I described this site to a friend as "the best place I know to spend time constructively when you should be working". But it occurred to me that I don't know the exact way to describe what we're doing. Mark Twain said "work is whatever a body is obliged to do, and play is whatever a body is not obliged to do", but we're not exactly playing. On the other hand, I wouldn't (unless desperate for something to put on my CV), call it voluntary work. Is there a word or short phrase for what you're doing at this moment?
Me personally, I'm edifying. And excogitating. Not necessarily in that order.
AFAIC, this question was perfectly positioned in English.stackexchange. It is not a discussion about the "behaviour" on the site, but a question about a word that can be used to describe the activity of the participants of the site. Hence, it is a question about language use and vocabulary.
I feel it should be moved back.
I'd say I'm "participating" in a direct sense, and "exploring" in a general one. I do agree with Twain, though: "play" is anything you don't have to do. Which only means you have to play like you work -- as profitably as you can -- and that too takes experimenting, practice and risk.
The main candidates for me are contributing and participating.
If I have to pick just one, it'll be the former. You could participate in Second Life, for example, without really implying you do anything to improve that site.