Honestly, the odds of BOTH the 7DII and a 70D being released are hard to swallow. I would see one or the other, but given the "failures" of the 60D to continue the legacy of the XXD series, I forsee the XXD line being dropped for a new flagship APS-C 7D mark II.
They won't upgrade the 7DII to full frame or APS-H (unless it supports EF-s lenses) and it doesn't make much sence to release TWO high performace APS-C cameras (which is where the 70D and 7DII would have to be placed) after the T4i.
The merging of the 70D and 7DII is logical. My guess with the sucess of the 7D, they will call the "new" camera the 7DII and NOT the 70D.
Just my 2 cents.
Well, since this is a rumor/opinion site, every opinion is valid if it has some reasonable number of neurons behind it. The above seems the most logical to me, depending of course on how one second-guesses the 7D intro. I'm not sure there is room to continue with four APS-C bodies xxxxD, xxxd, xxd, and 7D, so one of those has to go. I see the 7D intro as an effort to assert, or even experiment with, a near-pro C body and squeeze out one of the others eventually. The outcome of the 7D intro, it seems to me, was wildly succesful, which suggest that something with a 7 on the front will continue.
Marketing and customer messaging is both an art and a science, and moving the 7D itself to a FF sensor would drastically change the positioning of this body, as well as the market perceptions in ways far more profound than the merge of the APS-H 1D4 with the FF 1DS -- which itself was accomplished by droping the 1D<x> moniker altogether. So, just my interpretation of Canon's actions I would say 7D either disappears entirely or stays as the flagship APS-C body. and since the latter appears to have been Canon's intentions all along ,that seem the most likely outcome. Even a change to APS-H, as cool as that would be, would be even more confusing to today's 7D community who have already invested in EF-S lenses that would not work with such a sensor change. 7D owners would wanted to upgrade would be forced into the 70D or sell their S lenses. From a marketing perspective, the 70D name doesn't quite cut it, imho, as the flaship C body, when you already have 7D doing that already.
What's still conspicuously absent is an indication from Canon as to how they will fulfill their stated commitment to pro wildlife and sports without a 1.3x in the picture - unless it is with the combination of 1DX and 7D. and to do that, a new APS-C sensor in the 7D could have to produce better images than cropped 1DX images of the same FOV -- and do so more convincingly than todays 7D when compared with the 5D3. Such a (7D2) camera would have to reign as the premium flagship C body that the pros would be happy to carry as a 2nd body.
of course, we could see an APS-H surprise as well, which would be a fascinating show to watch on this board if it ever happend!