The new beta of Visual Studio 2008 and the .NET Framework 3.5 is just released and can be downloaded from http://msdn2.microsoft.com/en-us/vstudio/aa700831.aspx.
Most important for this release is that it includes a Go-Live license, which means that you can officially use this version in a production environment. I don't know exactly what other differences there are compared to beta 1 but I saw something about Partial Methods.
It is downloading now, but that will take a while I'm afraid...
BTW. Official release is planned for February 27, 2008 (also the date for SQL Server and Windows Server 2008).