Comment 5 for bug 445026

It happened to me on karmic after installing either desktop-switcher or activating compiz. I don`t really know which one for sure.

This is how i solved the problem. Switch back to the netbook-remix interface (if you wishe to stay with it). Deactivate every desktop effects. (That's weird but this is how i solved it) Install fusion-icon. Click with right button on fusion icon, set metacity as window manager and gtk as window border.

At this time the gnome-panel should have came back again. Close any program. Go to System->Preferences->Sessions.
Click on the Options tab, and then on the button "Remember the software currently under execution" (this can be different since i am not using it in english)

It should work properly now.