I was pondering a review and rating site, but some of the inherent problems:

–People who reviewing without experience with business
—–How could one *easily* verify this user should be able to rate?
–People who purposely review multiple times out of spite or subversion
–Liability of businesses coming after you for negative comments
–Making sure people do not falsely claim to be a business or person

Quite some deep business problems in the model…