I’ve just bought a new Mac with 10.8.2 pre-installed. When I started it up for the first time, once I’d gone through the initial set-up, the App Store launched, and showed me an iPhoto update, and some system updates including Mac OS X 10.8.3.
I quit the App Store, set up another account on the Mac to be my admin account, and edited my main account so that it wasn’t an admin any more. I restarted the Mac, logged in with my main (i.e. non-admin) account, and opened up the App Store again to install the updates.
The iPhoto update showed up, but the systems updates didn’t.
I installed the iPhoto update successfully. I then changed my main account back to being an admin account, thinking that maybe somehow that affected updates. I restarted the Mac, logged in using my main account (now an admin account again), and re-launched the App Store. Still no 10.8.3 or system updates listed.
Any idea what’s going on? On my old Mac, running 10.7, my main account was non-admin, and I didn’t have any problems installing OS X updates.