Spaces, aka. Mission Control, aka. "whateverthehellthey'recallingitthisweek", is meant to multimonitor set-ups with a bunch of apps in preset places. Use spaces/missioncontrol.
Personally, I don't get full-screen apps at all and wish this feature would die a painful and horrible death. I'd love to see stats on its use, as I've never seen anyone who actually knows what its cryptic icon represents.
I use it almost exclusively on my 11" air. With limited screen space it is very helpful. And swiping directionally between fullscreen apps is more intuitive than cmd-tab.
But it is total garbage on a large screen, so I don't use it when docked.
My common use case is opening text editor in fullscreen on main display and terminal with tests and tail -f log on the secondary one. Using Lion's fullscreen mode could help me get some extra screen estate for the editor, were it done right.
Also, why force turning off the displays? After all, one can press the power button or dim it using brightness settings, if the need arises.
I use it on my 15" MacBook pro all the time, and really enjoy it. I don't have external displays, so it's a great thing for me. But as others have said, with an external display attached to yor Mac, it's absolute garbage.
Spaces, aka. Mission Control, aka. "whateverthehellthey'recallingitthisweek", is meant to multimonitor set-ups with a bunch of apps in preset places. Use spaces/missioncontrol.
Personally, I don't get full-screen apps at all and wish this feature would die a painful and horrible death. I'd love to see stats on its use, as I've never seen anyone who actually knows what its cryptic icon represents.