Since the iPhone came out nearly 2 years ago they have made absolute certain that they control all the technology that runs it. This means they can update the software and hardware whenever they want. (Unlike with Macs where they often have to wait for 3rd parties to catch up. Remember how many people held off on Intel Macs until a native Photoshop came out? They've made sure that nothing like that can hold up a new iPhone. Everything that 3rd parties make is controlled in safe little sandboxes that Apple runs.)
They have done NOTHING to compromise that ideology yet. Allowing these "Safari Skins" doesn't do that. Allowing 'fart' app doesn't do that. Coming out with the SDK didn't do it. None of the changes they've made betray that original plan.
Allowing flash or different browser engines WOULD compromise that goal.
So no, I don't work for Apple, but when they go way out of their way to do something for almost 2 years then yes, I feel safe saying that they'll continue to do that. If you think they're going to suddenly change their minds with no warning then it is up to you to explain why you think they'll suddenly do that. Because they've given no clue that they will. Do YOU work for Apple?