* http://docs.python.org/reference/datamodel.html covers new style and
old style quite well.
 However, for the sake of the reader who reads it top-down, it will be
nice to add internal cross references (to
http://docs.python.org/reference/datamodel.html#new-style-and-classic-classes)


* http://docs.python.org/tutorial/classes.html mentions old-style
without any hint to the reader what it's. I suggest to add a link to
http://docs.python.org/reference/datamodel.html#new-style-and-classic-classes.