I've discovered another interesting quirk between the way that IE and FF handle flash.

I'm building a site that has a huge (3200x2100) scrolling bitmap for a background, the site itself is 1000x570, so there's a pretty big scrolling area as well. It's basically a bit of a processor fryer, and no, it wasn't my idea.

Movie is set to 25fps and I get the following behaviours:

FF: When the background is totally at rest, nothing is happening except a tiny amount of code for the fps monitor. Processor use reads 0% and I'm getting just over 21fps, consistently. Now if I start to scroll the background, the framerate goes down, hovers between 16 and 20 fps. Processor use hovers between 65 and 80 %

IE: Same thing, and I get EXACTLY the same when it's at rest - 0% processor use, consistently just over 21fps. Now if I start to scroll, the fps goes UP to 23-24 fps and the processor usage maxes out to 99/100

Weird