it's a pretty cool new feature.
Good catch! I have seen the screen pop up before with 2.1, but I never knew how I got there
i found this out last night (after talking to VZN customer service who had ZERO idea how to get that screen mind you!) after searching the internerd. like yourself, i've seen the screen before and never knew how i got to it and never even knew this feature existed.
ahhh...been there all along...but in 2.1 it was in a 'box' and showed only the last 6. It is IMHO the best way to switch between apps if you have more than one thing going on!