Video marketing can be very effective, provided you have an interesting video relevant to your website.
Google creates new videos from time to time - For example, Google created this video for Google Wallet (which became viral instantly) for promoting their existing, and latest, services.
However, a lot of people use adult videos to promote their websites (by watermarking their links in the videos). Please don't do that.
Create a very good video for your website, and then post it on Youtube and Vimeo with attractive title and description. And, if you are lucky, you will get a lot of traffic from it.