What is the difference between Potato and Woody?

["Randolph S. Kahle" <RandyKahle@KahleAssociates.com>]

I have started reading details about Woody. (I am running Potato on all
of my machines with the 2.4 kernel).

I was surprise to see that the 2.4 kernel is "optional". This leads me
to a fundamental question... What makes Woody different?

Are there structure changes (layout, etc.) that are incompatible with
Potato? If not, why not just keep upgrading the packages.

-- Randy