I can only speak for the student setting. When our PA class returned from winter break, about half of our class returned with PDA's. It seems to be pretty evenly balanced between Palms & Pocket PC's. I keep hearing that Pocket PC's are the "wave of the future" so I'm thinking about picking up an HP Pocket PC. They are indispensable, especially when you begin clinical rotations. Sure beats carrying around several different reference books in your pockets!
Monika =)