Heather Leslie (a.k.a @omowizard) on her concept of a universal health record:
A uhr is simply a non-proprietary pool of standardised health data which can be used for any purpose we want – PHR, EHR, EMR, SEHR, IEHR, research, epidemiology, reporting & stats, shared care, clinical decision support & more. There is no particular EHR application associated with it; in fact it works with any and every software program, vendor and healthcare provider.
She’s exactly right. I think the shortest analogy is to compare it to Twitter. Twitter provides a core set of data (user accounts, tweets, and some meta data), along with the APIs to access and manipulate them. Anyone is free to develop software that takes advantage of their framework, as long as they agree to certain rules of fairness and privacy.

The result is a diverse marketplace of Twitter apps. Some of them offer the full set of Twitter features (Twitter, formerly Tweetie for iPhone), while others focus on one particular aspect (Peephole for iPhone). If something similar were developed for health records, it would allow both all-encompassing EMRs and more narrowly-focussed apps (medical imaging comes to mind) to be useful in any context. Hospitals could switch EMRs without being trapped in a proprietary data-silo. Best-of-breed software would rise in market share based on merit instead of technical limitations.