That is quite fantastic. I produce my contributions in this forum with a paltry 6 megapixel camera.
I'm looking at purchasing a first gen 5D, thinking that the jump to 12 MP would be a great leap forward for me. Still, that doesn't hold a candle to the 21 MP 5D mk 2.
I've produced a few panoramics, but my high number is around 60 or 70 images. The large, featureless areas are always the most challenging to deal with. Regardless, it takes a lot of work to assemble one of these, so thanks for the effort. I think this image really raises the bar, so my hats off to you.