Also, apparently Google apps backup is broken for some users. I had a problem with the phone not sleeping and traced it to google backup, apparently it's a common problem with ICS. This is unrelated to contacts/calendar sync. If you have the phone device rooted and use titanium you can leave this off, and as long as you don't lose your phone it's no big deal. Setting is under system settings -> backup and reset.
Figure I would show this off here, had the flu last week and was basically comatose for 30 hours. Only about 2 hrs screen on time, but all radios on and even passed out with navigation on after checking traffic at one point. 51 hours
Sent from my SPH-L710 using xda premium