The second beta version of Visual Studio 2010 and Microsoft .NET Framework v4.0 are now available.  VS 2010 and .NET 4.0 deliver significant new capabilities and improvements.  The Beta 2 release was focused on performance, stability, and the integration of the overall feature set.  The development team is awaiting our feedback on the product and preparing for the final release candidate (RC).  Beta 2 includes a “go-live” license, which means you can start using these tools for your production projects.

VS 2010 and .NET 4.0 are slated to be released on March 22, 2010.

Download VS 2010 and .NET 4.0 Beta 2
More details about Beta 2 from Scott Gu

The good news is that Microsoft .NET Framework is installed on a majority of Windows PCs.  The bad news is if you are developing an application with the newest version of .NET (3.5), nearly half of Windows PCs cannot run your app.

Story at DevTopics