Courier is tempting, but two screens are going to make it uncompetitive for the market, and besides, dual screens are not really apt for a computer interface. As an ebook reader, yes, but I don’t think Microsoft is looking into Pixel Qi technology for it. Traditional LCDs are a reource drain, and two of them on a portable device is bloody battery murder.
The dual screens allow for one to be used as a virtual keyboard in clamshell configuration.
This should extend the life of the product, since wear on mechanical keyboarsds is a high failure point in todays “No moving parts” low power portables.
Someone at CES had a prototype where one of the screens was E-Ink, but I can’t recall who.