SharpGL 2.0 has no P/Invoke - all native functions are called by a C++/CLI class library (OpenGLWrapper if you're getting the code from CodePlex) which calls functions directly. This means there's no more importing of PIXELFORMAT structures and so on.
The thinking behind this was that a C++/CLI wrapper is faster than P/Invoke for a talkative API like OpenGL - but is this actually the case? In my new article on the CodeProject I investigate the performance differences between these two methods.
http://www.codeproject.com/KB/dotnet/pinvokeperformance.aspx