I'm curious, does the MBA have adequate enough cooling to keep the CPU from throttling down it's speed in full load situations? I got curious when I started to play around with iMovie and noticed when I first started the encoding process the timer showed 16 minutes. A couple minutes later the fan cranked up to full speed (or what I assume is full speed) and not long after that the timer started to INCREASE instead of decrease. I don't have a lot of experience with iMovie since this is my first Mac and maybe this is a known issue with the inaccurate timer. Being around PC's so long though I do have a fair amount of knowledge on how Intel CPU's work and the increasing encode time to me seemed like a byproduct of the CPU throttling down.