Jonathan Zdziarski, an iPhone hacker, says nothing has been blacklisted as of yet. However, the mechanism is there, and the iPhone could call in on occasion to see what has been blacklisted. Zdziarski says that Apple could have the ability to shut down applications you've purchased from the App Store.
While this may sound like a privacy violation, our sources tell us that Apple has put this tool into place as a security measure to shut down rogue apps if needed, and it could simply be a proof of concept that hasn't yet been implemented for actual takedowns. We're not convinced that this is new, considering that the only entry in the unauthorizedApps list is dated "2004" and is clearly a test entry.
[via Engadget & Macrumors]