Okay, so I'm finding myself puzzled by this. I have a 1.67GHz G4 PB and a 1.66GHz CD MM. I've used both to encode a DVD project in iDVD, and I'm astonished to say that it seems that my PB is the faster of the two! I do know why, sort of, but it doesn't lessen my surprise. I have menu meters so I can watch processor usage, and it seems that iDVD isn't very good at taking full advantage of both cores in the CD. So, it's more along the lines of a single 1.66GHz Core versus the 1.67GHz G4. And the results are that the G4 seems to outstrip it. Could this be in part because of the "Velocity Engine"? Just wondering, and wanting to share my surprise with all of you.