--- Operating System, Graphics card ---

Blender 2.66a. Any Mac with OS X 10.8 will show this.

--- Short description of error ---

Native apps in (Moutain) Lion create a new workspace when entering fullscreen. Blender doesn't do that.

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---

- Start a Mac with OS X 10.8
- Launch "Preview" and open an image
- Go to "Fullscreen"
- Notice how this creates a new workspace, and also adds a "back to windowed" button next to the clock in the menu bar.
- Launch Blender 2.66a
- Enter fullscreen
- Notice how it doesn't create a new workspace nor adds a "back to windowed" button in the menu bar