I recently rented a car from Enterprise Rent-A-Car. In their post-rental email to me, they sent me an email with a link to YP.com and asked me to review them on the YP.com web site.
This is a simple way to INCREASE reviews from satisfied customers.
Online reviews are a powerful way to increase sales, as before people buy from you, they often check out what others are saying about your product or service or company.