I guess I don't view this as a technology problem - more of an 'economic demand' issue. Looking at the evolution of email (and I know this is a simplification)... There were lots and lots of proprietary walled-garden email solutions pre-Internet. They worked fine for what they were - electronic memo systems for corporate users. The Internet changed the game, of course, and all those corporate users became interested in inter-operability - i.e. Company A want to exchange emails with Company B. My perspective is that email standards only gained real traction because of this economic imperative. People were willing to pay for email inter-operability and vendors were only too happy to adopted technology standards to make some money off their products. Where instant messaging is concerned, I don't think we have a economic imperative to drive a market that can pick winners and losers. Interestingly, there are plenty of walled-garden IM platforms in corporate use - e.g. Lync, Groove/Spark, etc. There is some amount of demand for inter-operability, but it's minimal in my experience. So without an economic impetus to standardize - here we are.

You can already just email your money in Canada. Anyone use this service? http://www.interac.ca/consumers/productsandservices_ol_emt.php