VST.NET allows VST Plugin developers to write Plugins in any .NET language. It makes the transition between the C++ and .NET world smooth and easy. The Framework built on top of the interop layer provides a clear and structured architecture accelerating development considerably.
VST.NET has been extended to also provide support for writing a managed VST Host. The VstPluginContext class (Interop.Host) allows you to load and communicate with unmanaged (and managed) VST Plugins. For managed VST plugins there is no (double) marshalling overhead and calls are made directly between managed host and managed plugins.