On the Cranks Brothers web site I noticed the rebuild kits for the 03's are different. Are the pedals different? Is one better than the other?

Absolutely!!!! They made some very good changes for 03. The new ones have much better seals and grease ports which make maintenace a snap. They also added the option from stainless steel spindles in addition to the Ti options. My 02s are a little loose but still going. I will likely replace with 03 SS sometime this year.