Monodevelop contains a kind of TODO list that lists all comments marked as TODO. It would be gratly beneficial to allow including NotImplementedException occurences on the list - such as Resharper's TODO list does.

This feature would be VERY helpful in doing test-driven development, since it allowsquickly answer the question "what next?"

Another reason is that you don't want to have NotImplementedExceptions in your final production code, so it's good to keep track of them.