This is a completely new feature given by visual studio 2005. Before Ajax was difficult to implement in a web program application. Atlas makes the life very easier by giving a complete framework to work on. We can discuss here about the pros and cons of atlas driven website.
I've used Atlas for some parts of my site. One thing is currently it is pretty weak on the drag and drop panel part. I'm sure once Atlas is out of beta it will rock. The latest Atlas Control Toolkit is looking pretty sweet if I must say.
I as of yet havent started using ATLAS and i am a big user of microsoft technologies. Im currently using ajaxpro.net for all my sites, mainly because im use to it and it does the job really well.. Ill be looking at investigating it in a couple of months or when there are more people out there using it.. If you guys have atlas sites let me know what they are, id like to see what atlas can do.. Regards
This is one of the pages I used Atlas on - http://www.webmasterbucket.com/Layouts.aspx It avoids a page refresh when you navigate via the DataGridView Pager.