The problem with Apple is that they signed an exclusivity agreement with a single carrier. I'm sure that if Google told Verizon, "The only place an Android phone will be for the next four years is Verizon", Verizon would jump through hoops for them.
But by getting the phone on all carriers, yet still doing 90% of what Apple is doing on a single carrier is impressive.
And MS has taken this a step further with the hardware requirements and no skinning, and one centralized market. Yet, they're doing this across all carriers.