If 70D rumour is true then it is a higher spec body than current 7D, so will Canon discontinue the existing 7D model, not very likely imho, especially since they retained the 5DII, despite the introduction of the new 5D3.
Also putting the 1DX/5D3 AF system (61 point) into a 7D2 body + dual-Digic 5 processors would pitch this new body against the 1D4, I mean you're talking 10fps (maybe 12fps) with the added benefit of a little extra reach.