In the demo, Corporate Vice President of Windows Phone Program Management Joe Belfiore uses pinch to zoom/unzoom. Isn't the "pinch" gesture to zoom/unzoom patented by Apple? (and that's why Android doesn't use that gesture--as far as I know):

 

"According to the US Patent Office Apple was awarded patent number 7,479,949 on January 20, 2009. The patent which was filed on April 11, 2008 covers multi-touch and all associated gestures such as pinch, swipe and rotation."

 

from http://news.worldofapple.com/archives/2009/01/26/apple-awarded-multi-touch-patent/