Well, my logic is this.
If 2.0 comes out while the AH is still up and running, people will be more inclined to push for item hunting so they can throw as many of the new items as they can get onto it. It also seems like players will be able to make more gold in RoS (bounties and rifts, and higher level), which means the AH prices for these new items will be crazy. This will make the gold difference between AH and non AH users even greater than it is now.
This is far from fact, just what I figure. So don't take me up on it word for word, it's really just my personal musings.