beta 8

Try the following Terminal command (quotes not needed.): “softwareupdate -d -a” If there are any updates availble, this should find and download (but not install) them. To install, once download completed, you can either check for updates in the App Store app, or, issue the following Terminal command: “softwareupdate -i -a” If you use the Terminal command, it will NOT automatically restart. You will need to manually restart your Mac. The installation during restart also has a graphic screen if you use this second method, as opposed to just the Apple logo screen when updating via App Store.

The best thing to do is to go to the download section on developer.apple.com and download the installer to update you Mac.