Gamescom is drawing to a close, and with it a flurry of developer interviews have been taking place. One which happened just a couple of hours ago was a raiding-specific round table with Game Director Tom Chilton and Lead Content Designer Cory Stockton. One of the questions asked related to the much-debated item squish, and whether we would see it in WoW 6.0. Tom and Cory responded as follows:
TC: "If we don't do the item squish it's going to require a lot of re-engineering of our combat code to actually support bigger numbers. We're getting really close to the point where the code can't..."
CS: "Yeah, the code can't compile the numbers"
TC: "Yeah it can't compile the numbers, so we are testing the item squish internally with the expansion, and I think a good time to launch it would be right before the next expansion so people are already used to it by the time the expansion launches. So, that's the current plan, but we'll see how it works out. I hope we can."
Of course that isn't a firm confirmation, there have been many changes, certainly ones of this magnitude, that have gone into internal testing and not ever made it live. This is no cast iron guarantee. But, the devs mention how their combat code is nearing the point where it can't actually handle the big numbers, and it seems that a full expansion of item level escalation would do nothing to help with this issue. So an item squish certainly seems extremely likely for the next expansion.