Video is primarily for entertainment, text is for conveying information. At least on the net. Newspapers don't seem to understand this - a lot of them are starting to have videoclips on their sites, apparently to grab marketshare from TV. It's much more expensive than writing an article, and it doesn't work. There are, of course exceptions: "nipslips", catastrophes and such call for video, but most news don't.
The original post is great. I'm sending it to all my journalism buddies.