One of the best improvements with HTML 5 is its ability to play video. Previously HTML alone was not able to display video so solutions such as Real Player, Flash, and Quicktime have been filling the gap. To play HTML 5 video you need a modern browser which is a problem for those of us dependent on an IT department within businesses and enterprises. For instance I'm sure many of your companies are still on Windows XP and Internet Explorer 6 (both released in 2001).