VSIP 2005 has been available a while, but I hadn't found the time to look into it. Now I did and I must say I'm impressed, especially by the new managed classes in the Environment SDK. For example, it's now possible to create a custom editor for Visual Studio completely in C#, and creating a tool window in managed code is really a matter of a few lines. Great work, I'll have to have a much closer look at this managed stuff!