I've already started two non-Minecraft threads in GamingNova, and a lot of the OMG 27 Minecraft threads are spun-off discussions from the original mega-long Minecraft thread, and aren't necessarily active. They'll fade from view with time.
I do agree that, since it's a general gaming forum, threads that are about Minecraft should say so in the title. Most of them do, but there's a few ("Project Gallery," "Spider Chat," the mob trap poll) that don't.
Edit: Aaaand they've been edited. So, there you go.
I agree that we should give the new forum a chance to grow before writing it off as only for the Minecrafters. E3
is right around the corner, and a gaming forum is something that's made a lot of sense for some time now. Everybody who was complaining on the Twitters should just start a Myst thread and be happy.