I can’t help myself. It’s probably worth noting that nobody knows for sure what these options do, and you might do serious damage to your Mac or your App Store account by playing with them. But … just a look can’t hurt … can it?
- Quit App Store.app
- Open Terminal
- defaults write com.apple.appstore ShowDebugMenu -bool true
- Relaunch App Store
Enjoy it while you can. I’m sure it will be gone in the next update, especially if anybody at Apple sees this post.