Jay Cline in Computerworld has taken a scoot around the web to see how the most popular sites stack up with respect to privacy. The yardstick he used to measure are the Safe Harbour principles for compliance with the European Union Privacy Directive. I'd suggest that he use the ten principles from the Canadian Standards Association Model Code for the Protection of Personal Information, but the Safe Harbour Principles are a good place to start.
Safest Places On the Web - Computerworld:
His findings are well worth the read.