I always check out the top 25 free apps. I have gotten hooked on Cubes Lite.

I don't use Twitter, so I can't help there - but the Facebook app, the Woot app (if you're a fan of woot.com)...

called "wootwatch"...Google Earth, Quickpedia (wikipedia)...Pandora... TapTap Revenge...AroundMe...and I like WordSearch.

thanks guys! This was really helpful!