I've had two 5D2's for a couple of years now. Shoot every weekend, and process through the week. I bought a 7D in December on a whim. I'm selling it on eBay soon. I'd describe the image quality as "sub par" or "horrible" depending on what kind of mood I'm in. A shame - the features and handling are top notch.
Image Quality, Features, Low Price (in comparison to 1D/Ds) - pick two of the three!! OK breaking it down
IQ + low price = 5D2
features + low price = 7D
IQ + features = 1Ds
Now off to sell my 7D.