The padfone is such a great ideas for those who want both a tablet and a phone. All tablets are just oversized smart phones and it will be great to just simply put your phone into a tablet dock to increase the screen size and battery life.
The popularity of this will depend on the price of the dock, hopefully around $200. It would make more sense to spend around $500 for a phone and $200 for a tablet dock rather than $500 on a phone and $600 on a tablet. Plus you can save even more money because you only need 1 Sim card with a data plan rather than 2.
Hopefully the specs will be competitive too dual core is a must, can't wait for further announcements.