Although I am not in the thick of things right now (because I am onsite, alone, so far away from my team) I follow the very active kanbandev yahoo group. It's a great resource for thoughts and questions on lean and kanban software engineering.
David Joyce, a group member, posted about a presentation he gave and I found it really good. So here's the presentation for anyone else interested.
It's definitely a long one but take some time to go through it.
Good stuff David.