Windows 8 and MultiUser Support
You have followed reviews of Windows 8/Surface one common theme you notice is most of the reviewers failed to even mention the superb MultiUser support in Windows 8.
Good news is Microsoft Watcher Paul has written a good article on it :)
Bad news he gets it wrong on App sharing :(
Following are couple of good features not addressed in above article
1. App Sharing: Say, for example, that your family has a shared PC. You have previously used your Microsoft account to purchase a game that all your kids like to play. You can install it for each of your kids by having each of them sign in to their Windows accounts on the shared PC, then launch the Store and sign in to the Store using your own Microsoft account. There, you’ll see all your apps and you can re-install the app on your kid’s Windows account. Installing apps on multiple user accounts on a shared PC still only counts as one of the five allowable PCs where you can install apps. (I tried this on couple of PC works very well)
2. Installer Sharing: If you have downloaded and installed an app and suppose if the user2 on the same PC tries to install the same app. Then Windows8 doesn't redownload the app, it will install it directly from the copy downloaded by the user1.
Source : Windows Store Blog