I would be interested to know how far will Cars.com go to protect the integrity of the reviews. It is extremely easy to create positive reviews for yourself (and negative ones for your competitors) - and without an method for checking the validity of the reviews, Cars.com might find itself play "cop" on a full time basis. If a review can simply be posted based on a phone call or email (or lack of either) it looks like it would be very easy for those inclined to do so, to manipulate the system.