i don't think the 7D is replaceable at the time being. its the cornerstone piece of canon marketing . the 1dx and 5dmk3 seem to fill in the space that the 7D created. I think the 7D is that camera that was meant for the high end enthusiast but not not pros. explains the price . anything below the 7D is for amateurs , anything above is for pros.
First of all Canon is running a business and 7D was, is and will be one of the best selling body ( like 5D2 or even better).
The key feature of the 7D series is his crop frame sensor ( EXTRA REACH) in a pro lvl body.
Today Canon don't have any more an APS-H sensor. In my opinion there are two possibilities:
1. push a little more up in class the 7D2, and fit it with a APS-H sensor; and extra features for the 70D to compensate today 7D
2. Keep the APS-C sensor in 7D2 , improve the noise and the others features.