To help customers develop Ajax style architectures, we released the WebSphere Application Server Feature Pack for Web 2.0. The latest update is 1.0.0.1 which was released in September. If your trying to get your arms around this technology. Here is a great list of items that will be helpful:
The Web 2.0 Feature Pack is supported on WebSphere Application Server version 7.0, 6.0.2, 6.1 and WebSphere Community Edition 2.x
The name says it all: IBM RedBook "Building Dynamic Ajax Applications Using WebSphere Feature Pack for Web 2.0"
A number of good overview articles:
A look at the WebSphere Application Server Feature Pack for Web 2.0
Create Ajax-style architectures with the IBM Web 2.0 Feature Pack
building enterprise SOA Ajax clients with the Dojo toolkit and JSON-RPC
There are tons of other articles on IBM Developer Works. Search on Dojo or Ajax.
The all inclusive IBM InfoCenter for the Web 2.0 Feature Pack. The Web 2.0 Feature Pack also includes the documentation in the download as well.
The Dojo Toolkit 1.1 makes up the client side programming model for the Web 2.0 Feature Pack.
Dojo Toolkit Site
Dojo Toolkit documentation campus contains an ever growing list of in-depth documentation.
While you can use Rational Application Developer 7.0 or Eclipse to develop applications for the Web 2.0 Feature Pack, RAD 7.5 has useful integrated support, including WebSphere Application Server 7.0.