The big challenge I see would be building a totem that had theora but
didn't have all the patent and license encumbered non US friendly formats. It would require major violence on the innards of xine-lib it appears.
What about totem + gstreamer? It seems there was excitement about this a while ago but I have not heard any news for quite some time. I have seen no mention of totem on gstreamer-devel lately.
-- Mike