Earlier quoted context omitted.
The web didn't had at first a common format for images ... but now all modern browsers have support for GIF, JPEG, and PNG. And it was probably a smart move on their part to avoid political issues. Apple will add Theora support if the demand increases. Mozilla will add H.264 support when the IP-issues are cleared.
Is there a moment to "clear" the H.264 issues? I have the understanding that the people who own the copyright are making plenty of money off of it and it quite a popular format. I don't see why they would give that up.
(As an aside, don't cast this as a FF vs. the world, patent fees kill startups as well as open source companies.)