A common usability mistake people make is that they assume that everyone has the latest version of the Macromedia Flash Player installed. While 90% of people do use have the Flash plug-in installed, not everyone has the Flash 6 Player or even the Flash 5 Player installed on their computers. Should a user visit your site using an older, incompatible version of the Flash player, you could end up inconveniencing the viewer to the point that he/she never returns to your site again! Not all users use Internet Explorer with the cool Install On Demand feature that automatically downloads the plug-in if the user does not have the plug in installed.
This is a companion discussion topic for the original entry at http://www.kirupa.com/developer/mx/detection.htm
