With AutoCAD 2012 there are some changes affecting the command line and text window.
The command history is by default distinguished from the active command line with a grey background color. In Options>Display>Colors>Drawing Windows Colors dialog box the Command history background, Command history text, Active prompt background and Active prompt text colors can be changed.
Vertical and horizontal scroll bars only appear when hovering on the right side or bottom right. I first though this was a bug, not sure it is such a good feature.
This may not add much to the reason why AutoCAD 2012 is better than previous releases but I think having another color on the history is a good thing.