The world's reaction is also negative. They don't want to wear a box strapped to their face to interact with their friends. Seriously, look at the reaction on Twitter by non-gamers and Facebook users. It's being met with incredulity and mockery.
They don't want now, but wait 'till Facebook does "their magic" on them :) That "networking effect" stuff is not buzz-speak, and they know how to wield it.
Plus, gaming and socialization go hand in hand - it's amazing that others just don't fucking get this yet and see "gamers communities" as just niches or islands.
Their new audience isn't quite as easily convinced to invest hundreds of dollars on a piece of dedicated hardware.
They already had that audience - down the line, once they have established their beachhead. Selling themselves to facebook doesn't bring it any closer.