It's clearly a Windows desktop in the picture. The only "confusion" I could understand would be in that he copied a stock OS X wallpaper to the damn thing.Yes, but either way my original question is still valid, which is driving the screen in the picture?
Have you never seen an LCD with multiple inputs? Mine, for example, does DVI, VGA, Composite, and S-Video. I have the PowerBook plugged in via DVI and the PC via VGA.