"Telepathy is likely to work the same way for messaging. Right
now, telepathy has real backends for text, voice, and video. It
handles quite a few protocols through its own plugins and virtually
everything else though libpurple (from Pidgin). In a couple of
Gnome releases, we should be seeing Evolution, Ekiga, and Empathy
in a giant symbiotic relationship. Suddenly, you will see that the
person you're emailing is online and accepting IM/voice (but no
video), and you will be able to click to start the conversation.
This isn't too much different than the way GMail works now (and is
a killer feature), but the desktop integration will be complete,
meaning an easier time communicating for the Gnome user."