Infonaut's Journal: Is MPEG-4 "good enough" for Open Source users?

Some people feel that MPEG-4 is inherently evil because it is encumbered by patents. Given that tools for transcoding to and manipulating Ogg Theora are sometimes difficult to work with, how many Open Source users/advocates simply refuse to use MPEG files (not to mention QuickTime and Windows Media) they come across on the Net? Are a very small number of users making a big deal about this, or is there a widespread feeling that Open Source users have an imperative need for a patent-free video format? If so, what are the tangible benefits of Theora for users of proprietary operating systems?