I think I remember reading somewhere that the average GPA for CC is around 3.3-3.4. I believe that the cutoff for cum laude in CC is usually around 3.8. I'm sorry I don't have more information about SEAS.
Beard tax (SEAS guy who used to post here) estimated it to be around 3 a few years ago. Most SEAS upperclassmen I've talked to here put it at about 3.05-3.1 based on % A's on the transcript and engineering classes that curve to a B.