Sun started working on a lot of AJAX things about a year ago. As the manager for the Java Web Tier, that meant that I was pretty involved with most of the work we're doing. But for the most part, we kept quiet - in large part because we don't like to preannounce things.
Well, we're now far enough along to talk about things - there' quite a few different things in particular that we've announced this week that merit special attention:
The old standard of the Blueprints Petstore has gotten a new look, in the new Java Petstore 2.0 EA - with lots of AJAXey goodness. If you haven't checked it out yet, you should. The Blueprints guys have also been working hard on all getting out all kinds of AJAX related information, including a nifty set of JSF AJAX components, that are also usable in Java Studio Creator...
There's also JSF Dyamnic Updating - this is a JSF extension library which divides the page into zones, and allows partial updating of pages through these zones.
And of course, there's more on the way - watch our main AJAX page to hear more.