So here it is: the very first '5D Mark II' picture I'm posting. Let me welcome you to the full-frame/fisheye age on fluck.de with a slam dunk by Kareem Maddox of the Princeton Tigers.
About the lens: It's the Sigma 15mm 2.8 fisheye. It's a little less expensive than the Canon counterpart, but at the same time it's built nicer and produces a little bit better images - at least that's what I read.
I also read a lot about the 5D of course, so there were no surprises on that part either. This is an ISO 6400 picture. I'm all set, that all I need for now.