I’ve been a long fan of the XMPP protocol and I’ve started implementing it using the fantastic Kamaelia. With all the GSoC discussion around it appeared that lots of people were more and more interested in seeing XMPP becoming the natural partner of HTTP in the maze that the Internet has quickly become. Consequently Peter Saint-AndrÃ© created today the Social mailing-list to all people interested in discussing how XMPP could be used in what is that social web of yours.
I’m totally biased but I think there is more to XMPP than IM, the protocol and its suite of extensions provide great power applicable to RIA, whether they reside inside our outside the browser. For instance, I do believe that rather than using Comet one ought to use XMPP to push notifications to the client. In such a case one might consider the client as a node in a cloud of lazily interconnected nodes and then start thinking of the browser as more than a HTML rendering engine and without the resort to abuse HTTP for things it was never meant to support.
I wish browser vendors could start implementing XMPP within the browser as that would provide a fantastic incentive for more applications based on the power of XMPP.