it only really matters how you use it
of course IRC and XMPP are two entirely different things. but as far as a regular user, like me, is concerned, they're the same general idea. XMPP is just... better
as far as I can tell, they're even used about the same amount these days :P
not actually an edit: I just looked at it a little more and it seems even more like IRC than at first. a bunch of different servers, and a bunch of different clients
it seems pretty cool actually. shame it isn't widely-used yet
an actual edit this time: I think the name could get confusing though, with XAMPP and all
well, IRC servers don't federate, XMPP servers do, which is a big difference
the reasons why i think XMPP is awesome are mostly that it's an open protocol and that it federates
that it federates, like email, is great because it makes it impossible for one authority to have control over the network
it is widely used, but mostly under the hood (fb chat(non-federated, though), gtalk, …) so most people don't know they're using it~ :3
XMPP came before XAMPP :P
