Not necessarily
One of the great strengths of Android is how much you can do to change up the interface (including changing it to mimic WinPhone7 or iOS). Sites like Lifehacker often spotlight particularly clever/innovative/attractive Android layouts, and there is some honest-to-God artistry there.
The Windows Phone 7 interface is striking, sure, but it's also a little too bold for my tastes...I try to have at least some open space on my Android's home screens (which have a great landscape photo I took as the background). And iOS is just old.