It's finally hitting the street - "Advanced ASP.NET Ajax Server Controls"
I had the pleasure to be a technical reviewer on this book during the writing process and am really excited about it's release.
This book if one of the few that dive deep into the framework, its architecture and extensibility, and address the power-user/developer scenarios and it does it from a controls perspective. It's a big undertaking but Adam and Joel have done a great job.
As Nikhil said "If you're building applications in Ajax today, and want to take that to the next level, you'll want to look into the platform deeper beyond the out-of-the-box features i.e. its extensibility. You'll specifically want to build reusable components and controls, on both the server and on the client. Check out this book on more details like "the client script framework", "the script application object", "localization" and "the control toolkit" amongst many other relevant topics".
[ Get a copy HERE ]