Just like you, I'm waiting patiently for Gran Turismo 5 and after hearing that it'll be delayed AGAIN... I decided to throw together a PS3 wallpaper.
It's all 3D. Logo traced in Photoshop, exported in vector to Illustrator and then imported into Max (I know - just draw it in Illustrator... no... lol).
Had to redo the GT part with a poly-modeled piece, but the text worked out ok just with an extrude.
Rendered with mentalray, caustics enabled (obviously).
Looks like a bit of wireframe on the back of the GT text, but that's from the caustics.
Hopefully it'll help take the edge off for some people... works for me.
If anyone wants to use it in a theme (later on), please just let me know...
Download for the 1080P version.