Two good features, others nixed.
First... Batman!
The batman light feature is pretty cool, but perhaps as suggested above, hold ctrl while mousing over it; I would suggest pausing over it for a pre-determined length of time, adjustable by the user to always on - some # of ms/sec - or off; also as you pause over it having the window peek itself onto the screen with a an outline (as if it was floating) would be nice to see in my opinion.
Next...
Taskbar on all connected screens? BRILLIANT! Wish they'd code it in! Set the primary monitor's taskbar to normal and have the ability to add/remove/adjust the taskbar on other windows. This can be done in Delphi or VB2008 code easily!
As far as the F9 all windows come up and F11 all windows disappear, it sounds neat for photo-editing/viewing applications; for everyday applications like surfing the internet, not so much.
Future integration into 3D monitors on the next OS would be wicked, use spatial grid projected in front of the screen or over an area in which the user can fully manipulate would be awesome to see instead of a fixed 2-d monitor made to look 3d, users could take their apps into a full 3d environment.
What I would LOVE to see, but I doubt it will happen; Microsoft buying Mozilla - and FIREFOX! (This post written from Firefox!)