Understandable, but still, when it comes to comparing how IE 9 stacks up to "Firefox" on rendering engines and memory usage, it doesn't seem particularly meanin

Understandable, but still, when it comes to comparing how IE 9 stacks up to "Firefox" on rendering engines and memory usage, it doesn't seem particularly meaningful to compare the brand new IE 9 to the old Firefox just because IE 9 released a single week before the next major revision of Firefox is slated to. Not that you were writing a New York Times article here or anything. :) I certainly understand your other point about the single-process design.