I was playing around in ”Settings” and pressed ”Change PC Settigns”, to see if the Metro Control Panel is the same as in Windows 8. It is, more than that, it has the options of changing the background color of the Metro UI, the lock screen picture and the user accound picture. I could not bring a picture as background as in Windows 8, but it seems that the Desktop Experience feature contains more than I was expecting.
Those features are unlocked once Server 2012 is activated. You then will be able to change pic, background colors and also lock screen and so on.