From their site:
Deactivate Final Cut Studio
If you want to install Final Cut Studio on a different computer, you should first deactivate it on your computer to avoid serial number conflicts.
Use the Deactivate Final Cut Studio command to remove the licensing information without uninstalling Final Cut Studio.
It's similar to FCPRescue from the BeforeTime™ and free so maybe it's worth having around although it does nothing that can't be done manually in the Finder. There is a screenshot here, which shows Final Cut Assistant being a menubar item which is a nice idea.
Maybe one day Apple will just include some of these basic functions from within FCP itself, just like iCal has a Backup and Restore option under it's File menu.