Ran into @KyleNPatel@nimeshg and @sati at Dreamforce. Young company with a lot of potential.
We've tested out sending video to customers the moment they signup at MailLift (http://MailLift.com). We didn't track the results, but people liked the videos :)
WIth @OneMob, they make it super easy for salespeople to send video mail to prospects and customers from their phone. It looks like they can track the efforts in Salesforce as well.