Portability versus size is an important consideration. My notebook computer is neither small, or portable. You really need a cart to carry it long distances.
Tara's iPad is smaller but still not very portable.
Carrying a tablet is very much like a hauling a notebook computer.
Finally the PlayBook. It is ultimately portable yet it is as wide an old fashioned iPad.
It also has more usable screen area thanks to margin gestures.
And contrary to what I initially thought, the PlayBook is good in meetings.
You can get work done but in an unobtrusive and subtle way.
A notebook computer or old style iPad screams:
"antisocial" and "I am not paying attention".
The PlayBook is much less in everyone's face.
It whispers: "I am still listening to you..."
Yep. The PlayBook is Practically Portable™.