.NET is Microsofts attempt to make its programs platform independent. All Microsoft Visual Studio languages have been modified to output the same intermediate language. This intermediate language can be compiled and linked at run time on whatever platform and operating system Microsoft decides to support in the future. In theory at some future time Visual C++, Visual Basic, C#, etc. code could even run on a Mac or UNIX platform. All it will take is a compiler/linker that will take the intermediate language code and produce a native executable.

This has little benefit on code that will only run on one computer. The greatest benefit will be for client/server and other applications that can potentially run on different platforms.