Right now, nothing. That's not why this is important.
Think about the consequences of this for just one moment. How much support and developer time is Firefox going to lose if it can't play videos if/when YouTube switches over fully and doesn't use Flash? How much support and developer time is Linux going to lose if there are no browsers for it that can play internet videos, if H.264 becomes the de-facto standard (note that only Chrome works, not Chromium)? If you don't care about that at all, and are happy using IE (or Chrome, these days) on Windows for ever, then by all means move along, there is nothing for you to see here. The rest of us care.