After upgrading to 10.3.9 over the weekend, my LaunchBar installation stopped working. Specifically, it couldn't complete the "Indexing Applications" step of its startup process. I emailed Objective Development and got this in response:
Mac OS X 10.3.9 seems to introduce a new problem affecting LaunchBar's ability to scan for all installed applications. In most cases it seems to help to rebuild the LaunchServices database of Mac OS X. Delete this file:Worked perfectly.
and restart your computer. Please let me know if this helps to resolve the problem.