Visual Studio is not a "fun" program like Halo or Fable. It's a productivity application akin to Microsoft Excel. You use it to do work. Adding achievements to it is a way to break up the monotony of typing all day and to encourage developers to branch out and try new things in the application.
Making Visual Studio achievements part of Xbox live kind of misses the entire point: Visual Studio is not a game, and the "achievements" in Visual Studio are really just fun ways of exploring the application for people who are working.