Just so you guys know on my E6400 Snow Leopard 10.6.1, sleep still works with Zpilot's IOUSBFamily.kext.
I'm booting from EFI partition with Chameleon 2 RC3. In addition, USB still works after waking up but with the warning that it has been unplugged and then it reconnect.
Edit: Wifi works after waking up but not the on board NIC
You have accelerated graphics, 10.6.1 and sleep? Are you using the vanilla kernel?