I’m going to mark this as completed so you can get your votes back – note that Matthew Johnson has released a VS 2012 color theme editor as you requested (link below) – I know it doesn’t have everything you requested in this idea, but hopefully this helps to address your feedback.
Doug Turnure – Visual Studio PMNick commented
@Anna; I thought you looked familiar after coming across your codeproject earlier in the day... I've pretty much determined the data structure and extracted the color codes. I have yet to look at the structure of VS 2010 to see how they compare but that is left for later as my focus is on VS2012. I'm looking to see if the icons can be statically done as it would be less of a "hack" and more of a natural and permanent approach. Thanks for the suggestion, I'll get in touch with Carlos.Nick commented
@Tom; I've started work on theme customization for VS2012. I've got pretty far by sheer reverse engineering approach as I don't think any documentation exists on this. I'm at a point where I can modify the colors of every component in the IDE so far. I'm now working on the icons.. Once I get there, rolling out a VS2010 theme or something similar would be pretty easy. Stay tuned.