The “Atlas” June CTP was release while I was at CFUnited. As Scott and Nikhil point out, this is primarily a bug fix and UpdatePanel enhancement release. The UpdatePanel enhancements open up a bunch of new scenarios to use the UpdatePanel where it wasn’t possible previously. The short explanation is that you can add UpdatePanel controls to the page dynamically at runtime. Check out Nikhil’s post for more details. Scott also talks about a few new controls coming in the soon to be released build of the “Atlas” Control Toolkit (which will use the June CTP). You can download the “Atlas” June CTP here. The release notes for the CTP are here.