Apple caused a bit of a stir this week when they rejected an app made by the band Nine Inch Nails. The application connects users to information about the band and their upcoming shows, in addition to social 'fan connecting' features and streaming music. Due to “objectionable content” in some of their songs, Apple rejected their app.
Trent Reznor spoke out against Apple's actions. The content that Apple had issues with was all contained on songs that were separate from the app (and songs that Apple had no issues with hosting on iTunes). Response from NIN fans was so great that Apple was forced to reconsider their initial decision. The NIN app was successfully accepted today, unaltered from its original form.
In the iPhone 3.0 beta released yesterday, and age-based restrictions were added into the app center, in order to ensure that children under a certain age can't access inappropriate apps. The addition of a parental control system was a way to allow Apple to start hooking up with more...mature apps. Adult content is okay with Apple, as long as they can say they're keeping it where children can't access it.