Bashiok added a follow up to his Bind on Equip/Bind on Account comments from the new Blizzcast, which at least confirms that things haven’t changed since they recorded it. A fan asked about the BoA issue, and pointed out that eventually everyone would have lots of the best items locked into their account, where all of their characters could use them and that this would kill trading. Bashiok agreed, and elaborated.
It would probably stagnate the economy… UNLESS, there are other systems in place that could make it attractive for players to essentially destroy their BoAs. So I don’t think it’s without solution at least, but it could get sticky if not balanced or pulled off just right.
Anyway, we’re not really seriously considering BoA items at this point in time.