Will the social gaming leader be the next great IPO? The New York Times’ DealBook has a pretty tough piece on the company’s numbers-obsessed culture, and worries about potential talent dilution. Frankly, I thought the most damning bits were the stories of rejected mergers. Michael Arrington, of all people, responds that start-ups are hard work, so quit whining. Earlier, BusinessWeek saw some signs of sluggishness in Mafia Wars 2, and had some observers speculating that gaming fatigue might be setting in, meaning higher customer acquisition costs. Or maybe it’s just a dull game. Zynga’s growth depends on new hits, but BusinessWeek is correct in suggesting its ad revenues might need more focus if virtual goods sales are flat. Meanwhile, Electronic Arts is getting more competitive in Zynga’s space.