Informatics has high growth near term and high profit potential, but any service that will minimize hospital stays or outcomes is bigger (which does include constructive use of collected and relevant information). Billions have already been made in the last two years in preparation/deployment of profitable ACA strategies and there will be billions more. Actual delivery of care outside the hospital will also be big but more of a grind rather than fast bucks. Getting rich slowly is cool too!
I didn't bother with your poll because it looks like you want to know about larger trends, and your answers appear geared to a single worker. Education? Let's be serious.