powerbook is a system apple touts to be a great portable dv editting station. As we all know, DV editting requires tons of screen space, hence the ability to add a second screen to all pro models. Apple would be stupid if they did this to a powerbook. They need the pro market and this would hurt their standing in their market.
Obviously the person who started to spread this as the next powerbook is a brainless jackass. It might look cool, and may in fact be a future apple product, but its definitely not a powerbook like all of the mac forums are proclaiming it to be