Despite my repeated recommendation not to use nifty effects, many people want to use videos. So, here is how to do it right.
Who Watches Videos?
According to research presented by Guo L. Chen and colleagues at WWW conference 2005 in Chiba, Japan, most internet users stop watching videos after the first 10 seconds. This is most likely because people decide whether a video is worth watching or not within the first 10 seconds of watching it. Even if there is information in a 5-minute video that viewers would find interesting to view, if they don't find it in the first 10 seconds, then they will stop watching it.
Short Videos
Unfortunately, you cannot tell what kind of content is in a video without watching the video from the start until the end. This is something that internet users rarely do. So, instead of making a long all-in-one video, make some short one-topic-per-video videos. Then, put them up with a good self explanatory index. The "About Google Chrome" 
page is a good example. There is an index of videos on the left-hand side so that people can easily understand which video is about the feature they want to know. Also, each video is about 15 seconds long. This is the proper length based on Guo's research.
Video Isn't Everything
However, I still say that the foundation of information is text. Use video only if text cannot explain something, and limit the content of video to what text cannot explain. Video is only part of a web page; you need to think of the web page as a whole. You need to understand the advantages and disadvantages of video (image or text). Then, make sure you use them where they are best suited. This will make the performance of your web pages the very best.
© February, 2009