On Facebook, I have a personal site, which is mostly for my students and friends, though I see some writers/publishers are finding me there. Better would be for you to join as a fan of the NewPages Group. Matt Bell is more in charge of that, and posts notices of when new book review and lit mag reviews are published, and you can write on the wall there.
NewPages on MySpace is purely NewPages stuff – loads of publishers and magazines and writers we know. I keep that site updated with info about book and lit mag reviews.
Other than those, the NewPages blog and NewPages home page are really the best feed into what we’re doing here, related news and updates.