[iamjustlooking]

I really wish lion didn't make your second monitor useless in full screen.

[webfuel]

It's not completely useless, you can "click and drag windows and toolbars from the primary display to the secondary display"

http://osxdaily.com/2011/08/11/multiple-displays-full-screen...

[chc]

As far as I can tell, that piece is really deceptive. You can drag floating windows from the same application that would normally float over the fullscreen app. You cannot, for example, fullscreen TextMate on your primary display and have Safari or Photoshop on the secondary.