If other people are producing prints and even 100% crops that cannot be discerned from 5D2 shots, then perhaps you are doing something wrong.
In the conditions the most favor the 7D, with a bit of noise reduction and maybe some blur tool on the bokeh, I can produce prints that are very close to the 5DmarkII. It takes a fair bit of work though, and my time is valuable. Alas the conditions I need my 5D2 aren't very friendly to the poor old 7D, and no amount of work will save the 7D image under those conditions.
Can you pass a double blind test and tell us, with 100% accuracy, which prints or crops come from which camera when both are shot/processed to maximum potential? That's all that matters.
If the shot is straight from Camera with just basic levels adjustment and no noise reduction, I will pass this 100% of the time. If it's conditions that favor the 7D (i.e. don't expose its weaknesses) and someone works the files over a lot with Lightroom and photoshop, then it's anyone's guess (see above). If it's conditions that expose its weakensses, then even with a lot of 'shopping, I'd be able to tell the vast majority of the time. My eyes and grey matter have had daily exposure to the images produced by the 5D so I'm backing myself on this one.
For properly processed, low to mid ISO shots there are no significant differences. Yes, there is a difference out of camera with neutral settings, but nobody I know shoots or prints that way.
Even at base ISO, the 7D images require more work though to match the 5D2, but yes no 'significant' differences under the conditions that most favor the 7D....and they are properly processed.
{edit - actually even in bright light - I remember going around shooting with the 7D and the colors weren't as rich as the 5D and the dynamic range was notably less - not sure if this counts as 'significant' or not}
The 5D2 pulls ahead at high ISO, though the 7D does quite well through 3200 for normal print sizes. Oh yeah, I just had my yearly eye exam (20/10).
First part is true. My opinion is the 7D is pretty horrible at ISO3200. Everyone has different thresholds / standards of what they find acceptable. Funnily enough I am partially blind in one eye and require glasses, yet to me the differences are readily apparent. My good eye with glasses is pretty sharp

Better monitor?!
Rumors are rumors and this 7D rumor is probably rubbish. But...if Canon fails to answer the D800 and fails to continue their pro crop body, Nikon will eventually get my money. Will Canon still love me then?
Canon will correct their lineup with an updated 70D and leave the xD to the full frames. Notice how Nikon don't have a Dx model that's a crop? I'm sure Canon won't ignore this market segment - the crop zealots. I'm not too keen on the D800 though. Canon will check the sales on that and react accordingly if they need to. The 22MP 5dx/III will be wildly popular though. I will be buying two.