How do you have a feeding frenzy when you can’t—officially, at least—see what’s being served? This is the strange dynamic that runs through the flurry of Chinese debate this week about Facebook. In China, the site’s I.P.O, on Friday, is not simply an event; it is an existential problem—an object of admiration, envy, and, from the government’s perspective, suspicion. In Facebook’s shadow, there is also a persistent question about the weakness of Chinese innovation.