RIVWorks and Adding Video to E-Commerce

A company called RIVWorks will add video to your e-commerce Web site for as little as $79 per month. They use stock greetings taped in advance by actors. I guess the idea is that having someone greet you in person, with a voice you can hear and a body that is animated, will cause you to stay on the site longer and explore purchase options. I wonder if that is really true? What do you think?