At the Python level, all reference counting should be taken care of by PyGTK and gnome-python themselves; there is no need to ref()/unref() GObjects in python code. If you encounter a reference counting problem, most likely it is a bug in the code, with the following exception:

• There is a reference cycle between the python wrapper and its underlying C object; this means that the object will not be automatically deallocated when there are no more user references, and you will need the garbage collector to kick in (which may take a few cycles). This occasionally causes the odd problem, such as with pixbufs described in FAQ 8.4

Note that while gnome-vfs objects are not based on GObject, and implement their own reference counting, it's the same from the point of view of Python code: nothing needs to be done. A significant difference in gnome-vfs objects is that they do not allow the programmer to add new attributes or subclass them. Also, they don't have reference cycles, so they are deallocated without help from the garbage collector.

Bonobo objects are GObject based, but they require manual reference counting. There are well defined rules for ownership semantics in remote calls: [developer.gnome.org] . However, for in-process bonobo API calls, there are no rules, and you have to be very careful with the ownership of the references obtained on a per API function basis. Unfortunately the API itself is underdocumented, so...