I think multimedia can be extremely valuable to a web site. It all depends on the site and the users that come to visit the site. When considering multimedia for your web page you have to consider the users that are coming to your site and if they would be receptive to it and if there browsers can handle the bandwidth necessary to run video.
Too much multimedia can leave your visitors annoyed with slow page loading times. And if usability is not considered you run the risk of losing your core visitors and distracting from the content of the page. Using multimedia on your page is a fine line that you must continue to walk as your site continues to grow.