I've always found it quite interesting how giving something a name seems to make it "real". Case in point? AJAX. When I first [heard][adpativepath] this term, I thought to myself, "who really needs a specific term for a mishmash of technologies that's been around for a long time?" Well, as is often the case, I misunderestimated the importance of having a mental "handle" for an otherwise complex concept. And just like LAMP, it's not the specific technologies that are important (the 'P' in LAMP is heavily overloaded, just as the 'XML' in AJAX isn't as important as the idea of communicating directly with the server).
I don't know if I particularly care for the appelation -- particularly the XML bit -- but that no longer really matters. The name has probably stuck now that the WSJ has an article that opens with the words "Meet Ajax, the technology powerhouse." So it's settled, the concept has a name now.
And I believe it is a good thing that some kind of name has stuck. For some time now, I've found that everyone has their own ideas about what "rich" means to a web application (or if you're more into Flash, an internet application); and it just takes too long to try and explain "it's like the difference between Hotmail and Outlook".
Should be fun!