I'm following the 7D because I want a new camera and want it to perform very well with low light. 5D MkII is amazing but expensive. 7D seems nice, but noise might be a big issue. Camera has made it into the hands of people who are knowledgeable on this subject. Short summary from DPreview:
Note: I am talking about the RAW images.
The 7D is excellent in the noise department.
The "read noise" on pixel level is equal to or slightly lower than the 40D and 50D with ISO 100 and 200. From ISO 400 the 7D is somewhat better, and ISO 3200 (the top useful ISO of the 7D with raw) is quite better than the 40D.
All that is with 80% more pixels.
However, there is no question: this is far from the 5D2. Pixel (sensel) size does matter.
[Source = http://forums.dpreview.com/forums/re...read=32880471]
So Canon did do some magic to the pixels