The original 7D was originally billed by canon as a Pro level APS-C... heck at the time had better AF than the 5d2... Could be the same here...
At this point, unfortunately, I am not expecting big strides in IQ between the 7D and 7DII. If recent releases are anything to go by, I think we should lower our expectations.
Given that the 7D's weather sealing and AF were already better than the 5DII, I expect the likely level of improvement to the 7DII will be smaller than the difference between the 5DII and 5DIII. The difference between 19pt AF and 63pt AF is much smaller than the difference between 9pt AF and 63pt AF.
As a result I expect to see less reason to move from a 7D to a 7DII than from a 5DII to a 5DIII.
Those people who had a 7D and 5DII and moved to a 5DIII will also have less reason to buy a 7DII, so unless Canon does something radical (for instance to court laggard 1DIV users who can't see the need for a 1DX) I don't see the 7DII being as successful as the 7D.
Part of the 7D's success was that at that time, the closest thing to the nikon D300 was the 50D and that was a failure in comparison by most measuring sticks... Then canon came out with their trump card, almost out of nowhere that had had as good if not better everything... From IQ (although debatable), video, ergonomics, FPS, AF cross points, etc... Even after nikon came out with the D300S, the 7D still came out smelling like a rose.... Now nikon has gone out in full force with their 5100 and anticipated D400, this will have tougher competition and may not be the reigning king like it was 3-4 years ago. Wifi would be a cool feature, but it isn't new and shiny, the 6D and so on had that... 63 point AF, well that obviously wont be something new... HDR, Video, etc... most features has been implemented before... As far as ground breaking stuff, i dont know if there would really be any real jaw dropping features unless maybe it does 4k video. I for one wouldn't want a flippy out screen, but touch screen with that dual pixel sensor may be nice to have... I think even if all they did was slighly raise FPS to 10-12, like what most people are expecting, cleaner ISO and IQ and sharper/cleaner video with less jello, that would be enough for most people with the original 7D to plunk down $2k.