I have updated the OP with information on the 1.0 release of dom3editor. I have fixed all of the bugs sent to me and made some upgrades to the parser to speed it up.
One thing I have added is the ability to create a PDF report from a mod that lists all of the changes the mod implements, including the old and new values. At the moment this feature is not really very useful, it's just a first pass at my goal of auto-generated documentation that is useful and nice to look at. My goal is to be able to generate different manuals ("Nation Manuals" that will list all of the changes that effect a certain nation or a "Monster Manual" to list all of the monster changes) in an easy to read format including pictures of sprites and translated mod values (Fire instead of "0", translated bitmasks, etc). You could print out the differences between the mod and vanilla or even the differences between two versions of the mod to see what nations are effected most by changes.
There are versions of the editor for Windows, Linux and Mac. This is an open-source project, so the source code is freely available. The project webpage is:
http://code.google.com/p/dom3editor