Comment 17 for bug 614088

To me, the main problem is if, while installing, you enable auto-login. This way, if the built-in driver provided by the distribution doesn't support 3D (at least nouveau - I don't know about ATI), you'll not be able to use the OS since Unity won't load. In this case, the OS should ignore the auto-login setting and recommend the user to log in the desktop edition and, friendly as it is at Ubuntu, install additional drivers that support 3D, required for Unity. Also, it can be informed to the user that doing that and restarting the system would resolve the problem with Unity.