The guys over at InfoQ have an interview (video) with Mary and Tom Poppendieck on Lean online.
The explain the heritage of Lean as well as the basic principals applied to software development in general and product management in particular. They explain some of the seven principles:
- eliminate waste
- amplify learning
- delay commitment
- deliver fast
- build integrity (in the product)
- engage the intelligence of the people involved
- optimise the whole system
They discuss some of those principles in more detail (my favourite one is the discussion on late decisions). They are positioning Lean to Scrum, RUP and CMM. They also have a open discussion on the constraints of applying Lean principles (I particularly liked the statement about the level you have to aim for and the discussion about Lean under contract).
You might also want to check out the Poppendieck’s website.