So Ximian makes Gnome packages. Some Gnome developers are working for Ximian now, so they can work on Gnome fulltime and get paid. The following comments are owned by whoever posted them. That's only an example. Gnome developpers arent evil since they work for Ximian.
Balsa is one of the community stuff.
As you can see, balsa exists since several years befores Ximian but Ximian has never tried distributing it. Or install the packages the Balsa team made. For Debian that is a constant event. This is what ximian is, their model is to add their own alterations and provide them out to the community. If you want to use their stuff straightaway you can do so.