Google has started offering experimental support for viewing Youtube videos using html5 in testtube. THis means that you don't need to have flash installed! The problem is that you can't take advantage of it in Firefox, since testtube uses the proprietary h264 codec for the html5 videos, while Firefox uses the open codec Ogg Theora.
So, vote for Ogg support on Youtube. You only need to sign in with your Gmail account.
Web should be open, using open standards and formats.
Spread the word about voting for Youtube Ogg support in your blogs, facebook pages, etc.