I'm applying to an MHA program with the intentions of "specializing" in Public Health Informatics (PHI). PHI is a growing field with lots of demands, and it will be around for a long time due hospitals changing from paper to electronic workflows. It's also a lot easier to gather data and turn it into meaningful numbers with the existence of electronic databases, so hospitals are utilizing this technology to better manage their patient populations.
What specifically do you want to know about the field? I'm currently working full-time for an electronic medical record company, so I know a bit about PHI and I may be able to answer some questions.