The thumbnail may be a real problem in case of using the gallery function in an article. There is no thumbtime parameter. So many previews (see http://commons.wikimedia.org/wiki/File:Introduction_to_the_RepRap_Self_Repli... or http://commons.wikimedia.org/wiki/File:Sympetrum_sanguineum_kurz.ogv) will be not usable within a gallery.
Thanks, Ingo (User:Pristurus)