IMO the iPhone isn't RIM's most feared competitor. I think the android phone is more apt to cut into the BB business. The iPhone isn't going to change (much). They pimp their app store and all the cutesy apps you can use to read golf greens check your bank balance with. Those are nice for people like me, but the business people really don't mess with that stuff. If they do they have a second phone for that. Iphone's Achilles heel is ATT's weak 3G network, and they'd pay a fortune if they could roll it out on Verizon today. Because they're getting shot at by the Droid, the eris, the Incredible and once you've gone Android you won't be back for an iPhone.
BB 8900 Tmobile, Moto Droid Verizon