Microsoft has released a public CTP version of Visual Studio 2010 and .NET Framework 4.0. They are the next generation development tools and platform for Windows Vista, the 2007 Office System and the web.
The CTP is only available as a Virtual PC image and is designed to experience the new development tools and platform. It is not a feature complete product. Download the CTP from the Microsoft Download Center.
For more information about Visual Studio 2010 and .NET Framework 4.0 visit the Microsoft MSDN Visual Studio website for an overview. Don´t forget to post your feedback on the related Microsoft Connect website.