What I find interesting is that the ISO range is the same as the T5i.... there really isn't much of a difference in size of pixels between 18 and 20 Mpixels.... I would have expected that if they had gone to a newer process that the ISO range would have exceeded the T5i, so my bet is the same technology as before for the sensor with further improvements to "live view" like we have seen on the last few lower-end releases.
I'm still expecting some improvement, though.
A 5DII-->6D type of improvement, where high ISOs (3200 and above) should be progressively cleaner compared to the 60D, for example.
Canon also said that it was to be the 7D2 that was the "game changer". That's when I would expect to see any signifianly better technology emerge.
It's only natural that new tech is introduced on higher-end bodies first.
Considering that Canon did a full refresh of their FF lineup last year, the 7DII is the best candidate right now for the new tech introduction.