me! i go from low end to high end android, the big major differences is of course the apps. amount of apps comparison is a lots, and bear in mind, almost all things is NOT FREE on WP7. That's a major setback. Even a simple game like angry bird need to buy, on android at least it's free but with ads, i can live with that as long as its free. And one more thing is the limitation of WP7, everything need to sync here and there, always need to reset phone in order to adjust some important settings like region etc, but i totally understand since WP7 is still young. Really hope the OS will get better. Other than that, WP7 wins hands down. 

You'll love the smoothness, the simplicity, everything that u ever wish for in a phone. WP7 is really simple and easy to use unlike android full of customization, good for modders.