There's a new Microsoft Learning Clinic called "Developing Enhanced Web Experiences with Microsoft ASP.NET AJAX Extensions". It takes about two hours to get through. I'd recommend it as introductory material. It even includes some good debugging tips, including using Nikhil's Web Development Helper in some ways I didn't know about.
There were a couple inaccuracies I noticed when I skimmed through this:
- In the section called "Building a Simple ASP.NET AJAX Application", the "Adding ASP.NET AJAX to an Existing ASP.NET Application" demo shows adding the validator tag mappings to web.config, but that's a big no-no with 1.0.
- In the section called "Calling Web Services and Web Methods from the Client", the "Calling Page Level Web Methods" demo failed to show that you need to add EnablePageMethods="true" on your ScriptManager.
Both of those are things that changed very late in the product cycle before the 1.0 release, so I imagine that's why they were missed in the MSL content.
Aside from those two points, the content looked very solid, and this is a great way to get familiar with the breadth of the product. Clearly a lot of work went into putting this together. The production quality is quite high.
What are you waiting for? Go check it out!