This summary of a very interesting report appeared a little while ago.
Physicians: iPad Not Ready For Clinical Use
Most doctors still use desktops because iPads lack speech processing capabilities. One expert, however, says iPad EHRs are coming.
February 02, 2012
Eighty percent of physicians in a recent survey said they believe that the Apple iPad has an "exciting future in healthcare"--but they doubt it is ready for clinical use.
The survey of 100 "early adopter" physicians by Spyglass Consulting Group in Menlo Park, Calif., also found that 83% of the respondents used desktop computers to access clinical information, whether they were in the hospital, in the office, or at home. Some physicians said they used mobile devices to retrieve healthcare data when they were traveling. 
Pretty much the same could have been said of physicians five years ago, when many of them used reference tools and calculators on personal digital assistants (PDAs) and smartphones, but few doctors looked up clinical information on those devices. Some physicians used tablet computers with their EHRs, and some used tablets or PDAs for e-prescribing, charge capture, or both.
One barrier to clinical use of iPads today is the attitude of hospitals. "Seventy-five percent of physicians interviewed reported that hospital IT [staff] was resistant to supporting personal mobile devices on the corporate network," the Spyglass release said. "Hospital IT believes personal devices are insecure, less reliable, and more expensive to deploy, support and maintain than desktop computers."
That finding jibes with other recent studies. But as the Spyglass report acknowledges, hospital security concerns are not the major obstacle to iPad use in clinical work.
"Significant software innovation will be required to realize the vision for anytime, anywhere clinical computing," Gregg Malkary, managing director of Spyglass, said in the announcement. "Clinical applications must be rewritten and optimized to take advantage of the native capabilities of the Apple iPad and other mobile devices including gesture-based computing, natural language speech recognition, unified communications, and video conferencing."
Malkary told InformationWeek Healthcare that, although Epic and Allscripts are both experimenting with iPad-native EHRs, he doesn't expect the vendors to go into production on these innovations anytime soon. The big barrier, in his view, is not the technology, but the vendors' reluctance to "redesign their applications from the ground up with a focus on patient-centric care."
The full article is here:
It seems to me that the security issue is really a furphy. There is no way it is not possible to render and iPad device attached to a hospital network just a secure as any other remote terminal.
The killer issue is how to create an iPad based data entry capability that works as well as the key board and mouse. Whether this will be with some voice based technology or other approach I can’t say but to be an EHR/EMR front-end there really does have to be a slick data-entry capability.
For information lookup what we have now is fine - but it really is only half the story!
David.