But of course, it’s highly unlikely that we will ever see this for various reasons. Apple are generally very restrictive with these things and they don’t like the idea of giving their users too much control, and on the other hand there is also the issue with liability if something goes wrong.
Companies on the Android market have already addressed this issue by simply stating that rooting a device will void its warranty, and Apple could also try something like that, although the different nature of the iOS crowd would make that a bit more challenging.
And there is also the problem with unverified apps. Part of the reason for jailbreaking an iOS device is to allow the user to load custom apps on it, but this is something that Apple would never allow for many reasons.
Not only is it not safe for users, but it will also cut into Apple’s profits from the App Store, and according to some, this is actually the main reason why we will never see this happening. Maybe with a revised App Store model, but that is also highly unlikely.