I lost all of my quick launch bar icons on my n9 when upgrading to PR1.1. While digging around I noticed reports that there's a bit of a race condition when using apps like Shortcuts to change the quick launch apps which can result in them being lost.

The file that gets broken is /home/user/.config/meegotouchhome-nokia/launcherbuttons.data - it should have the following lines at the end:

home\user\.local\share\applications\quicklaunchbar 0.desktop=quicklaunchbar/0
home\user\.local\share\applications\quicklaunchbar 1.desktop=quicklaunchbar/1
home\user\.local\share\applications\quicklaunchbar 2.desktop=quicklaunchbar/2
home\user\.local\share\applications\quicklaunchbar 3.desktop=quicklaunchbar/3

These are removed sometimes when the target files are changed, and especially if they're removed. You can either paste those lines in or copy the original from /etc/xdg/meegotouchhome-nokia: which will also reset the order of your icons in the launcher:

Then reboot. Killing mcompositor doesn't seem to do the trick.