Check out
this talk on Google Video for an introdocution to XML11.

Yahoo! has released an AJAX UI library and a set of Design Patterns. Here you can learn more about Yahoo! UI Lbrary ; and here you can learn more about Yahoo! Patterns.
“The Yahoo! User Interface Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications […]

A really interesting feature of open source is the ability to move quickly in response to user demands. According to this post, PHP will include the php-json module with standard distribution.

Numerous posts in the news regarding AJAX have sparked an interesting debate:
Which toolkit should I use?
Easy enough to ask, not so easy to answer. The sprawling growth of AJAX toolkits has reached a point of dilution. There are so many packages that claim to be THE toolkit it makes it almost impossible […]

Here’s one library that’s pretty nice: PAJAJ - they have some slick demos.
HTML_AJAX had its first PEAR release today. Its the same version as was voted on so there is no new code but you can use the PEAR installer to get it.
Once you have it installed you’ll find the examples in the docs dir […]