Thought i share a great free little app that solves the autosleep issue in SL.

I have a GA-EP35-DS4 Rev2.1 and Snow running very smoothly - only issue was manual sleep works great but not auto sleep.

This app solves this problem - now autosleep works as it should

here's the link to that app: http://www.dragonone.com/products/macosx/pleasesleep/