"One of the most important (and unique!) features of Windows Phone 7.5 is live tiles. Live tiles make Windows Phone truly recognizable, even if you see it from 10 meters away in a store. I created this cheat sheet to help you quickly add live tile features to your app. Enjoy!
You guys know me, the cheat sheets I don't like are few and far between... :P
Here's a few snips from the two page PDF;