I'm also still wrapping my brain around why all of a sudden Bitcoin is money to the US when so many prior incarnations of similar things are not money. The Feds have argued for a century that the only real money is the money they (or another government) print. Time and again rather than allowing commodities that act like money to exist, they have shut them down and denied that they ever were "money" or "currency". It's definitely caught me somewhat by surprise and the site needs to make some changes to co-exist in this new world order.
Because bitcoin is highly disruptive where all former incarnations of money-like tools were merely evolutionary at best. And unlike its predecessors, which they could kill without even acknowledging their value, bitcoin can't be shut down, they know that all too well. The only way to enforce their regulations on bitcoin is to acknowledge it as real and thus a real threat to their system. That way they can attack the bridges between fiat and bitcoin and make it as hard as possible to use. I think, for the first time ever, they are truly afraid of a competing system and they will do their utmost to keep it down.