Back in 80's electronic Mail, used to work only inside same network and protocols.
The reason was that the electronic Mail first appeared as a feature of proprietary communication platforms. Which usually is combined with market domination attempts.
In other words company A, didn't want to support company B, as they wanted the customers(medium/large corporations back there), to keep buying from the same vendor. Which used to guarantee long term agreements and easier support, as they were required to know only about their own solutions.
After some time the unavoidable happened, some integration companies started appearing. And after another period, some companies started using SMTP as a ready-to-use and plug'n'play platforms with out-of-the box interoperability with other networks, companies and vendors.
With TCP Protocol, we also had a time when Microsoft tried to force everybody into a crappy and proprietary protocol called InetBios. Which also caused same nasty effects before fading out.
The pattern always repeated:
1) Control Tryout;
3) Migration to a common and inter-operable solution.
It seems like we don't notice it, but, we are in the exactly epicentric(fase 2) point of the IM Monopoly tryout. The only difference is that it is lasting too long, as we have a mass of ignorant people that just accepts whatever the mass market push into their computer.
This is one of the most cruel monopoly ever! Proprietary IM networks REQUIRES you to have an account on their service in order to allow you to communicate to your friends!
In other words: "They make you drop your freedom of choice in order to keep in touch with your already converted friends!"
Stop this now! Start using federated or aggregation like nimbuzz.com and fight for your freedom putting pressure in order to speed up their surrender!
Never give up your Freedom!
Start demanding the same freedom that you have in or email service, phone, etc...!