To test processing efficiency - speaking strictly of the CPU, I decided to compare my 2011 MBP against the 2010 i7 iMac, just to see what the real difference would be when pushed to the limit. I ran a 25 minute encode through Adobe Premiere Pro - 1080p, 24fps, AVCHD. The results were rather interesting. First, CPU utilization. The MBP went to 100% utilization right after beginning and finished an hour later. The iMac never went past 65% utilization and finished 40 minutes later. Second, heat. The MBP got to 85C easily. The iMac never went past 65C. I'm wondering if the increased space, or the general design of the iMac - where heat can rise out of the top and away from the machine instead of downward like the MBP - helps on that. Question is why the MBP wants to use all cores to encode when the iMac doesn't, and why the MBP takes longer with more cores than the iMac with less. Curious outcome...not a negative, I'm actually intrigued by it.