They are just one of the 3 big providers. Argus is the PGP one I am most familiar with.
I don't know a lot about the inner workings of Medical Objects or the third one, HealthLink. I just hope their interoperability discussions end up being fruitful.
Would be great. Whatever they achieve, it will still be better than letters from one GP to another: we use BP, please send us the patients data in xml format. (Which may or may not load depending on what the other side uses)
