As Sean mentioned below, the new VS10 Editor was unveiled at TechEd EMEA this week. We are all excited to introduce the new VS10 Editor to the world! The VS10 Editor was designed with extensibility from the ground up, and we want to enable our customers to build cool extensions on top of our platform. You can view the Jason Zander TechEd EMEA session at http://www.microsoft.com/emea/teched2008/developer/default.aspx
Soma has a Channel9 session on the key themes for VS2010, and demos how the VS10 Editor allows for text view margin extensibility by showing off our Structure Margin sample at https://channel9.msdn.com/posts/VisualStudio/Soma-on-the-Key-Themes-for-Visual-Studio-2010/
Welcome to the new VS10 Editor!
Lead Software Design Engineer
VS Platform Team