Hey guys,
Just wanted to drop a quick line. I just installed the 10.6.4 update released by Apple a few hours ago, and when you reboot the computer is completely unusable with Displaylink installed.
Instead of the log-in screen, you are presented with horizontal lines going across your screen.
The way to fix this (for the rush of people who will have this problem
):
Reboot your computer
Hold the Shift key while booting to boot into Safe Boot
Uninstall the DisplayLink in Applications/DisplayLink
Reboot, and you should be OK, but DisplayLink-less.