There is a new article published by the AAP, warning against the 'method' aspoused by 'Babywise'.
You an find the full text at the link below:
http://www.drmomma.org/2009/12/babywise-linked-to-babies-dehydration.html
I'd steer clear of any measure that stresses scheduling. Breastfed babies do better when you feed on demand. The AAP supports this viewpoint.