[throwaway899]

I would really love that we all start using some open chat standard (Like XMPP) so WhatsApp, Telegram, etc. could talk to each other.

Or something like email, you could have [e-mail] or [e-mail] and that would be your 'chat address' and all clients could talk to each other

[SamWhited]

Even if it weren't federated (though I do miss Google Talk), there would still be some value in using an open standard. If I can only afford a feature phone, there are XMPP clients for it (or they can be developed relatively easily), even if I don't get all the features. Using open standards, even if you don't make the service open, still makes you more inclusive and helps a lot of people who would otherwise be shut out of your service.

[jhasse]

so ... XMPP?