ahsanford said:
I'll reiterate from other threads: the D500's mere existence is not enough to get Canon to radically change it's heretofore glacial refresh timelines for the 7D brand -- it needs to actually sell well.
Alastair Norcross said:
My point was simply that, when you take all aspects of the sensor into consideration, the improvement from the 7D to the 7DII is actually quite large, much larger than that from the 7DII to the 80D.
Agree with these comments, which I think sums things up nicely.
The main reason to update the 7DII would come from both internal and external market pressures.
Internally, the latest APS-C sensor (80D) is a nice improvement, but not huge. And, in fact any advantage disappears at higher ISOs, which is where the 7DII lives for many of its users. This isn't unique to APS-C, by the way. The 1DX II significantly improved low ISO dynamic range, but it isn't a big jump at higher ISOs over the original 1DX.
So, other than a desire to have the "latest" sensor, there isn't a compelling reason for an update. An extra year or so of sensor research and improvements would likely benefit 7D users more than a quick refresh.
Externally, one would have to know how much of a competitive threat the D500 is. We could debate that endlessly. If the D500 is a big seller, even that doesn't necessarily have any significance for Canon. The time between the 7DI and 7DII was nothing in comparison to the long-delay between the D300 and D500, which means there was a lot of pent-up demand for Nikon to address.
Looking at the side-by-side feature comparison that was posted some time back, there really isn't that much difference (Touch Screen, Flip Screen, Wireless and 4K) between the Nikon and the Canon.
For those who want 4K, it is a really big deal. But, for most of us it's not. Touch Screen and Flip Screen are nice features, but nobody is going to switch brands over that. If Canon offers an inexpensive wireless accessory, that could take care of that deficiency (Personally, I'd love to see a battery grip with wireless integrated into the grip).
The other differences are chiefly brand differences (Nikon vs. Canon autofocus and sensor performance). Canon isn't going to adopt either of these (they will instead continue to perfect their own versions), which again means patience will be a virtue.
Having said all that though, I do think it is entirely possible that a new 7DIII will surface before the end of 2017 or possibly in early 2018, which would be sooner than before, but not a rushed refresh.