When I resume from hibernation in Ubuntu 10.10 the screen shows static, very similar to what you see on an analogue TV that hasn't been tuned properly. This also occurs on boot from shut down, but only for a moment after the Plymouth boot screen.
The static lasts for at least 5 minutes. An odd thing that happens is that the mouse pointer, as a lighter square of static, becomes visible and you can move it around. Attempting to change into a terminal (i.e. ctrl+alt+F1) doesn't seem to work (and I'm not sure if that can be done from the login screen).
Resuming from suspend has different issues - vertical lines appearing for a second before appearing to be in terminal mode (blinking cursor) and then going to the lock screen.
I'm running Ubuntu 10.10 on a Dell Studio 15 with ATI graphics, however I'm not using the proprietary drivers as I had issues with dual-screen support, so it's the generic X.org drivers being used.