I can't speak to Windows Phone 7 in comparison to Android or iPhone....I've never seen a Windows Phone 7 in real use (by anyone other than a MSFT MVP or employee) -except for the tv spots MSFT bought INSIDE the storyline of too many tv shows....and that is probably a simulated screen!
JB and other friends/MVP have shown me their WP7. It's quite slick, no question....I'm not sure how it's better than Android (not saying it is or isn't...I really don't know).