Leo says to hold off on buying anything until after Monday's WWDC announcements. We're hearing the Macbook Pro will have retina displays and will be a lot thinner. If he's considering the 13", then the Macbook Air is probably the way to go.
Shawn also does video editing, and would use this primarily for editing purposes. For this, he probably wants the Pro. He'll get a much bigger drive in the Macbook Pro, and it will be marginally faster. The Macbook Air's do have fast processors, but the Macbook Pro has a faster bus, better video cards, etc. A 15" Macbook Pro, especially with the new Ivybridge processor that we expect, would probably be great for what he wants to do.