It can be found here. The biggest new features include integration with all SKUs of Visual Studio 2005, and support for Live on both Windows and the 360. The Visual Studio integration is huge, in my opinion, if only because it enables source control and add-in support for developers. I guess now you’re also able to use mixed-mode debugging for XNA projects, but I believe that is only useful for Windows-based projects — I can’t imagine that they’d ever allow unsigned code execution on the 360 (for security reasons). One can always hope, though. 😉
They claim that the final release isn’t far off, either. With Visual Studio 2008 having just been released to manufacturing as well, I would imagine that there will be a refresh for XNA Game Studio that will include support for 2008. (The 2.0 beta doesn’t seem to integrate with 2008, or at least Beta 2 of 2008.)