When I was in university, the teachers had absolutely no idea what they were doing, and so they would use the latest Microsoft format, which was the .docx, and you should have seen all of the students freak out because hardly any of them could open the files up or if they could it wasn't properly formatted. I had to show all of my teachers how to set it so that they would only send it in 2000/XP .doc format. What was surprising, was that nearly all of my classmates used MS Office, and yet they couldn't access Microsoft's OWN formats! One teacher even suggested downloading Open Office so that the files could be opened. Now, if that doesn't show how closed sourced a supposedly open format is, then I don't know what is!
If the hospital demands that all formats within the agency to be odt, then little by little this will start a trend amongst the end users because they'll see how easy it'll be to use this open format and won't have to go through all the bs that Microsoft puts them through. This isn't going to happen overnight, but it will happen.
I'm going to be volunteering at a non-profit organization, and they have a really old database program, and the executive director is thinking of using LO Base, so I'm going to push for it because if they can't afford the Microsoft tax they'll be able to move over to Linux with absolutely no interoperably issues:-)