Image by snackfight via Flickr
I’d rather be in FB’s spot than Apple's, though neither is really desirable. Apple needed to do act as they do for the first hundred or so iPhone apps to understand what was going on, and then they needed to get mostly out of the way. FB needs to get a bit in the way — but predictably, rather their current slapdash fashion.
Apps don’t need to be vetted. Developers do, but they can largely be checked out automatically. Any developer should be able to build an app and distribute it in low volume. If it gets decent uniques and/or views, the developer should be forced to provide much greater disclosure about who they are and how they operate. FB or Apple administrators may choose to look at this registration data for the fastest growing apps, but the users will QA buggy apps or vote down the problem apps very quickly. That process would identify the undesirable developers in no time. The same is true of adult content. Given a disclosure option, over 99% of adult content promoters will self-identify either because the huge majority are ethical, non-hypocrites and almost all the rest are just too greedy to risk being thrown off the system.
Also, as Hewitt almost says, a centralized, public bug reporting/tracking system for all apps would be astonishing. Best/worst bug fix rankings would drive interesting traffic to app developers.