Okay, I don't normally use Exposé, but today I hit F11, expecting all of my windows to scatter offscreen and expose my desktop (like it's always done in the past), but instead of doing that, this time it scaled down all of my windows into a little box in the lower left-hand corner!
I didn't change any preferences (that I know of). Did F11's behavior change in a system update or something? Is anyone else experiencing this or know about this?