I have a felling their will be multiple SKU's of this. I'm kind of betting on the controllers being backwards compatible with the NX. (I have a feeling the NX will be very much like the WII U except for you can take the mobile unit with you as a handheld, so the Wii U pad will be able to work as a local controller.
So there will more than likely be 3 SKU's for this, the expensive one with a Mobile unit and a console unit, one with Just the console unit and maybe a pro-type controller, and the mobile unit. (So maybe $450-to-$500, $300-to-$350 and a $150-to-$200)
Another thing to note is timing. If they don't launch until sometime in 2017, the console unit maybe under $300, which will allow the chips used in the units to go down in price. (I'm guessing they will "off-the-shelf" parts with minimal optimization for gaming only purposes.)
As for the Wii U's price they said the exchange rates are one of the reasons they haven't cut the prices since they don't want to get into the red again. Though I do think there will be a price cut early next year, if they are still in the black for the year.