Apple has moved Software Update from being a standalone application into the Mac App Store in the new beta of OS X Mountain Lion.
Now when you launch Software Update from the Apple menu at the top left of your screen the Mac App Store is launched and you are prompted to install any updates available.
Take a look below...
Now when you launch Software Update from the Apple menu at the top left of your screen the Mac App Store is launched and you are prompted to install any updates available.
Take a look below...