I have always wanted to try Windows Phone 7 OS for longer than an in-store demo. It looks like a useful user interface, but I was never too sure about it.
Microsoft has recently placed a demo of the OS online. It is set up to give every Android or iOS user a taste of the Metro interface. Try it out on your phone here: http://aka.ms/wpdemo
I walked through the whole demo. The front "tile" screen is pretty and notifications from each app on the home screen is nice. As I travelled lower into the menu system I found the text layout to be a bit messy. However, I do like that the lower your travel in the menus, the more specific the data becomes.
Hashing over Windows Phone 7 is old news, so see it for yourself, if you have not already.
Cabe