Also, as much as I like Apple and the Iphone, it won't be long before some companies will pick up on the concept and produce something very similar, if not better. If an operator allows revenue sharing with Apple, they will be losing to all the competition that will be able to pick up the new phones without revenue sharing.
There are some Chinese companies already producing some interesting copies. Not the same functionality yet but similar philosophy and in some cases higher resolution.
Depends on your faith in Apple's ability to produce a slick user interface.
ie. there's plenty of PCs out there so why bother buying a mac? It can be more expensive, is slightly less compatible and even has lesser features than the PC (laptop graphics cards anyone?). Apple still sell because OSX is very good (not perfect but good).
The same applies to phones.
The wrinkle for Apple is having to deal with the very competitive phone market and it's players.