A little over a year ago I write a convenient little code snippet to display the indices of vertices, edges and faces in the 3d-view of Blender. This is a big help in developing script that create or alter mesh topology, as you can now get visual feedback on what you're doing.
It was pretty clear to me that I had to port it to Blender 2.5 before I could do any serious work on scripts like LoopTools. So after a commit made it possible to draw in the 3d viewport using python, I ported it right away.
That was two months ago, so what's new? The script has been added to Blender Contrib. This means that it is kept up to date with all changes in Blender and can even be automatically included when you build Blender yourself. There have also been various changes to the blender api, for instance Mathutils to mathutils, and Vector() to Vector((),xyz) The script has been updated to reflect those changes. Big thanks to all the people at the Blender extensions project who helped with this.
Let me end with some links: