I know for a fact that some people already have functional AutoIT bots, and I suspect at least one person at Zelaron is using one. Possibly two.

Chruser, Hardcore mode does have an item sink built in, but it also has a separate auction house last I checked. It also will not have a RMAH based on my most recent information. I do suspect that eventually the AH will be flooded with cheap items because of the constant influx of items compared to the relatively small outflow. The fact that items don't soulbind means they pretty much never go away other than when someone quits the game (assuming they don't give away their items/account) or when someone sells/salvages an item. Perhaps Blizzard will incentivize salvaging set/unique items.