Actually I gave Gobby a try a month ago and thought it would be nice to have a collaborative plugin for Code::Blocks, but I still think SVN is a better choice.
The concept is interesting, but I found it quite problematic for source code.
If you feel like writing the plugin, go ahead. A really good open-source collaborative editor is still missing (Gobby needs more development and the plugin for jEdit was really problematic to get working).