Zynga is even more dependent on Facebook than we thought:

Zynga’s Facebook risk is enormous. Zynga is basically Facebook’s outsourced games arm. Paradoxically, it might be good for the stock short-term, because Facebook is still private and owning Zynga is even more a proxy for owning Facebook, so investors could pile in.
Over the longer term, however, this clearly doesn’t make Zynga look great. Even though revenue from Facebook games is increasing as Zynga gets better at monetizing, unique users are basically flat. Zynga’s interest is clearly to build games on other platforms besides Facebook, both for growth and for platform risk mitigation. But it seems Facebook gets to say on what platforms Zynga can and can’t launch games. Zynga is betting on mobile as its next big platform. Is GameCenter, Apple’s iOS gaming social service, one of the “social platforms” on which Zynga can’t launch games without Facebook’s say-so?

I’ve been struck by how quickly my Facebook has decreased since the advent of Google+, thus reinforcing, perhaps inappropriately, my skepticism regarding the importance of antitrust intervention in social media.