Just in case you missed it, I think around a month back Microsoft .NET Framework 4 was released!

The .NET Framework is Microsoft's comprehensive and consistent programming model for building applications that have visually stunning user experiences, seamless and secure communication, and the ability to model a range of business processes.

The .NET Framework 4 works side by side with older Framework versions. Applications that are based on earlier versions of the Framework will continue to run on the version targeted by default.

http://www.microsoft.com/downloads/d...displaylang=en