From the official boards (a non-official workaround):
Go to your "C:Program FilesSonyStationLaunchpadSWG" folder and then open the updatestatus.xml in Notepad. Now change the timestamp from 2003 to 2004 and save it. This should get rid of the scan at launch but it's still a good idea to run full scan once in a while and also change this back once they get rid of full scan.