If you are using h2def.py/codegen.py to generate Python wrappers for your GObjects do pay attention to these messages:
Warning: Constructor for <your GObject here> needs to be updated to new API.
See http://live.gnome.org/PyGTK_2fWhatsNew28#update-constructors
That has the consequence that you’ll have problems subclassing the wrapped objects. That page doesn’t exist but you can see the explanation and how to solve it here.
