I have dedicated the past few days to AJAX research. With a little help from Pragmatic AJAX, which did a nice job of demystifying Google Maps, I was able to create my own map application with no server-side code. It is still a work in progress, but it already has some nice features.
So, in short, AJAX isn't something that will be here a year from now, it is something that is here now, and very usable. Apparently I missed it up to this point because I was more involved with Drools and Sprog. Time to wake up and smell the coffee.