I like that Microsoft is completely owning the software stack, versus all the customization happening in the Android space. Big unknown whether Google will find a way to crank down on the crapware, lame skinning, and associated madness.
(I will say, for the record, that Android 2.2 on my Droid X was a world of difference better than Android 2.1. Battery life went from "barely a day if you never touched it" to "50% left at the end of the day, despite heavy usage." I'm also quite happy with the improved Gmail, calendar, etc. At this point, even if I could switch to a WinMo7 phone for free, I wouldn't leave because I really enjoy the quality integration with Google services.)