This is definitely questionable and very curious...
What would this device be used for? What 2008 problem would it solve or reduce?
We have smart phones for communication via voice, email, web, IM, SMS and for calendar and contact sync. An iPhone with corporate Exchange support would be the best PDA out there for me.
Most corporate road warriors are more than happy with their Blackberries or Treos. They aren't going to want a bigger device.
The larger screen says, "internet tablet", full screen video and possibly handwritting recognition. There have been internet tablets like this that have flopped in the marketplace.
Handwritting could be interesting. That is one of my only regrets with the iPhone, the lack of handwriting. The MP2100 had some pretty awesome HW that is now incorporated into OS X as Inkwell.