FroKnowsPhoto has posted a video asking (and answering) which Canon full frame camera he thinks is for you (plus the EOS 7D Mark II). Jared talks about the EOS 6D, 5D Mark III, EOS-1D X and the APS-C EOS 7D Mark II.
I agree with most of what Jared says, outside of the EOS 6D. I think for $1499 after rebates, it's still a buy now camera. A replacement is going to cost closer to $2000 than the current $1500 pricetag. We've heard that the EOS 6D replacement may go a bit upmarket, which could bring a higher price.