Health Data Management has an interesting story about the adoption of tablet PCs in health care.

Susquehanna's Tablet PCs aren't mobile so much as portable. The
delivery system has mounted the devices on carts from Ergotron Inc.,
St. Paul, Minn. The Tablet PCs can be used on their own, but nurses
prefer to have the storage space the carts provide for scanners, bar
code readers or patient medications, says Mark Watson, administrative
director of I.T.

This confirms what I've seen in hospitals. Tablets are too big and heavy to be carried around, and without something handy to place them on, they can easily get misplaced, dirty, or dropped. A mobile cart (or computer on wheeles - COW) is the ideal "handy place" for tablets - they're secured, away from patients, ideally placed for viewability, and you always know where they are.

Probably the only user group in health care that uses tablet PCs as they were originally conceived are some physicians. But even for physicians, tablets are more a personal preference chosen from a number of options, rather than the preferred solution.

The reasons for tablet PCs poor acceptance are obvious: you can't drop them, you can't wipe them down with disinfectant, and the internal battery doesn't last a shift.