Jeff, It seems to me that you have gone most of the way to making the identity and visitor code as clean extensions.
I would however add my own +1 to Ian's suggestion that you consider using paste deploy for both of these. To my mind that solves all the issues that have been getting in the way (should these be part of quickstart, how to add them to existing projects safely, when should they be turned on etc). It also makes them usable to a wider community than just turbogears which given that I think you have done a great job is a good thing. Regards Dave
