This upgrade will be necessary for anyone who views Youtube. The Adobe Flash Player 10 needs to be installed in order to get rid of the annoying message that tells to upgrade your flash player, at minimum.
Adobe Flash Player 10 has some new features, and if you do not download the upgrade, then you will not be able to view any videos from YouTube, period...
Some of the new features include the ability to extend rich web applications to mobile devices, custom filters and effects, and 3D effects For more details and to download to the latest version of the Flash Player, visit Adobe -here-