With the launch of Firefox 3.5, Firefox became first browser to support Open Video Format. Dailymotion also launched a section to host Videos in Open format. Firefox also awarded $100,000 to Wikimedia foundation to coordinate efforts on development of Ogg Theora and related technology.
Does it change anything for me?
Well, not much for now. The only difference you will probably notice is that you will not need any plugin to watch videos created in open video format. You needed plugins for other formats such as Flash.
Why is it needed then?
But, it would make huge difference to Video publishing sites. Open video format is completely free and open source technology. That means anybody can create and host video with the format completely free. That would encourage lot of new work without having to rely upon video sites such as YouTube.