No big deal. You may just have to restart the dock. Do this first: right click on the dock and click quit. Go to the start menu and re-launch it.
If that doesn't work, then right click each icon, and click Icon Settings. In the bottom right corner, click 'Default Icon' button. It should restore the old logo.
I use RocketDock and this has happened occasionally to me. This should solve the problem.Reason for edit: typo
Edited by Jay-P VIP, 10 January 2009 - 11:50 AM.