I don't have a good one-stop "Here's everything people outside the company know about Zynga" resource in mind, but my two secrets for keeping a finger on the pulse of social gaming are a) andrewchenblog.com (though he doesn't blog much anymore, which saddens me because it frustrates my hunger for testing/metrics inspiration) and b) Slideshare (It is amazing what goodies people give away at conference presentations and a huge portion of them eventually migrate to Slideshare.)