Wally sent me a copy of Beginning Ajax with ASP.NET (and why is Ajax proper cased, not all in caps?) and I've been flicking through it and have skimmed the first few chapters. I've already learnt things, which was a surprise to me, but then I've not really looked at the object/prototyping stuff in Javascript and it's way more powerful than I though. I really like the first three chapters, they give a really good introduction to Javascript and the DOM and will be useful to ASP.NET developers - both 1.1 and 2.0 - who haven't looked at any client-side programming.
Chapter 4 takes a look at XMLHttpRequest, which is a 2.0 feature. While most Ajax development will use some sort of framework, it's actually worth learning this stuff so that you understand how asynchronous, client-driven development works.
Chapter 5 covers XML, XSLT (ick) and JSON. While XML is fundamental, XSLT less so. JSON however is important to learn and is used by lots of Ajax frameworks; I was a bit non-plussed when I first saw JSON declarations.
Chapter 6 looks at ASP.NET and what sort of asynchronous ability the existing controls have. For example controls such as the TreeView already support asynchronous loading of data. This chapter also looks at how ASP.NET pages can handle tasks asynchronously (some good diagrams make this clear).
Chaters 7-12 take a look at some of the Ajax frameworks, including Atlas. This is the area of the book that's going to have the least longevity as these frameworks change requenctly. This is especially true of Atlas, which is still in technical preview and about to see some major structural changes. It's a good overview of the various frameworks and gives an idea of their capabilities, which would be useful if you are starting a new project.
Chapter 12 is a really important chapter and like all debugging ones, always gets left to the end. I've been guilty of this in the past and in some ways this is wrong - we should put this near the front so that readers know how to do debugging as they work through the rest of the book. That aside, debugging client-side has always been, err, interesting. This chapter gives a great set of steps to show how to debug in the client and the server, both essential when using asynchronous technologies.
The single Amazon review for this book is, I think, a little harsh; not bad, but critical enough that it may put some people off. This is a beginning book and as such will give readers a good understanding of the basics of Ajax style development. It may not stand the test of time, but then the technologies are changing rapidly; the essential understanding of the technologies won't change though. It's not very long book, nor is it expensive and if you've never looked at any of these technologies before it's worth a read.
Listening to No Wheels Blues by Chris Rea from the album Blue Guitars Disc 5