I'm not familiar with ATLAS, but I have played around with AJAX. I actually created a solution to the "disabling the back button" problem using it, but it did not work with some of the lesser used browsers so we did not implement it. So, in short, yes I think AJAX is definitely worth learning

Hi guys!
I created a control that works like an AJAX container. Basically the way it works is that all the ASP.NET controls that you place inside of the AJAX container will automatically become AJAX enabled.
For example, at the same website where I uploaded the control assembly, I also posted some tutorials on how to use this AJAX container control. One of the tutorials walks you through the steps to create an AJAX chat application. You will see that you can code the ASP.NET controls exactly the same way you do in other regular projects. The controls are placed inside of the AJAX container which turns them into AJAX enabled. This AJAX container also has a property called ShouldRefresh. When set to true, it will update the contents of all the ASP.NET controls inside of the container.
Another tutorial that I also posted at http://www.KYNOU.com shows you how to use this AJAX container control to add three dropdownlists onto a web form and make sure that their contents get populated depending on the picked value in the previous dropdownlist. Something like an auto dealer website where you can choose the make and then the model dropdownlist gets populated according to the picked make. This tutorial shows you how to do that with three dropdownlists but you could have unlimited number of dropdownlists.
I uploaded this control and posted some walkthrough tutorials at http://www.KYNOU.com
Check it out!