Have I a corrupted clone?-funny things with Software Update
 

My original Macintosh HD was only 250GB and was in need of an upgrade due to an ever increasing music and photo collection.
I purchased a 750GB hard-disk to replace it.
SuperDuper! was used to effectively "clone" the 250GB disk by copying the contents to the 750GB.
Everything appeared to be going smoothly, and eventually the task completed without any reported warnings or errors.
The 250GB disk has been removed and the 750GB disk is now the startup disk.
Apart from iPhoto crashing after approx. 10 seconds of being opened for the first four or five times, it appears to be ok now.
The strange thing is when I went to do a 'Software Update...' from the Apple menu... nothing happened. This is also true when the software update is done from the 'About This Mac' also via the Apple menu. A software update can, however, be done via 'System Preferences --> Software Update --> Check Now'.
Another strange thing is when I select 'About This Mac' from the Apple menu and click 'More Info...', iTunes opens and plays a song.

Hi; see my response to your support email -- I think you need to rebuild your LaunchServices database.

As you suggested, I downloaded and installed OnyX from the VersionTracker website.
Once all the initial verifications had been completed, I located the 'Rebuild LaunchServices' option and ran it.
A couple of minutes later upon completion, I was able to do the 'Software Update...' and 'About This Mac' as normal :D

Thank you very much for you help... my confidence has been restored ;)

Also impressed by the very rapid response.

Kind regards

John