Following some experimenting with Mercurial at my workplace, I've done some toying around and am now using it for the Level Editor. What does this mean for you? Well Google Code hosts Open Source projects and has support for Mercurial, so where better for me to try it out?
You don't know what Mercurial is? Find out!
And, then, if you wanna give it a try, feel free to check out the editor source code! The Google Code project is located at http://smtcleveleditor.googlecode.com/. For those who want a direct link to see the source, here you go. For checkout instructions, please click on 'Checkout' just below the Source tab.
I have tested the project file with Visual C# Express Edition with the XNA Game Studio 3.1 package installed. However I have not compiled it, but as far as I know it should be good-to-go.
This post, like my previous, is likely to fall on deaf ears.
Maybe if it doesn't we can convince Salty to make his Open Source =P
Edit: Oh. And I signed up for Twitter. Follow me if you want.