Verizon announced that they’d be releasing an app for a variety of devices that adds functionality for FiOS customers. For example, iPad users can watch TV on the device as long as they’re at home. More relevantly to our purposes, though: they’ll be releasing an app to allow some smartphone users to stream video-on-demand.
There is a catch-22 though: the app only supports select smartphones - namely, those sold by Verizon. While this isn’t stated explicitly (that I can see), the list of supported devices makes it pretty obvious: Droid X, Droid 2, WinMo 6.5, and the BlackBerry Storm. Even better, it seems that any movies purchased or rented can then be viewed on any available device - no limitations to just one device.