The New CS6 Interface
New from CS5, under Preferences, you can change the color of the interface. Adjust it to suit your taste. Preferences>User Interface.
You can also tear off tool menu items when there are tools hidden under other on the tool bar.
Within Panels, you can rename Layers, Brushes, Symbols, etc. without double-clicking.
On the Character Panel, you can scroll through fonts with the arrow keys.
The color selector in the Color Panel has been expanded to make selecting more precise.