You are correct, it is a standard 19" made just for you.
I got an email today about my new bike. Moots doesn't have any frames in stock so it will be made from scratch. I kind of figured as much, especially since they likely didn't want to carry an inventory into the end-of-year for tax reasons.
Now, I'm still getting the stock 19" frame -- albeit "to order" -- but I really don't know why. If the frame is being made specifically to fill my order, then why not go ahead and make it custom? They have my measurements and while they do match up with the stock geometry, surely there is a 1/2" here or a 1/4 there that could make the fit that much better. And, since the tubes will be getting cut and welded to fill this one order, would it really cost them any extra effort to, say, cut the top-tube a 1/2" longer or shorter?
I understand that some of the other custom bike manufacturers have done away with the custom upcharge (Moots upcharges $350 to go fully custom) for this very reason. As great as this bike is going to be -- and it will be fantastic, I'm sure -- Moots ought to get with the competition in this regard. It's one thing if they have a stash of frames or dozens of pre-cut tubes for this specific frame already lying around and they only need to be welded (which may be the case), but if my bike is coming from raw uncut materials, then there is no reason for them to not make a custom bike for the same price. Aside from the fact that they don't want to.