If I visit Area 51 it shows that I committed to the Gaming site. However now that it's in beta if I try to log in I just get the "This site is currently in private beta" page.
One thing that might be throwing this off is (as I found) my OpenID wasn't associated with my Area 51 account at the time that I committed to Gaming. But now that I've associated it, I should get access to Gaming, right?
(This also makes me think that the process of starting an Area 51 account isn't as smooth as starting accounts on other Stack sites, which seem to get associated with my OpenID without much effort.)