Not that I am in any immediate need of a right answer here, but I've lately seen some efforts to introduce the concept of "(distributed) version control systems" for geographic data. Some examples (that I know of) are the three whitepapers from OpenGeo (1, 2 & 3) and the "Geosynkronisering (geosyncronization)" project by Norwegian GIS Software vendors and the Norwegian Mapping Agency. I've also found this question here, which mentions GeoGit (by OpenGeo), and this question about version control in ArcGIS.

Being a developer I know (at least enough to be able to use them) how version control systems for source code (like SVN and Git) works, and my background in geomatics tells me that there are some unique challenges with geographical data that makes the approach not completely similar to the way source code (which is basically text) are handled.

So, my question is thus: what are the challenges when dealing with (d)VCS'es for geographical data, how would you solve them, do we need them and are there other attempts to solve these issues than the ones I've mentioned?

I know that the OpenGeo whitepapers will answer some of my questions, but what I'm really is after is a more "pedagogical" answer, in the style of "tell me like I'm a 10-year-old", so that I can refer people to a great explanation of the challenges and solutions that geographical data brings to the mix.

I hope that someone with some insight will take time to provide some thoughts on the matter, as I said I'm not currently looking to solve a particular problem, but this topic is one that interests me.

(Hope this is not a too open-ended question)