Yes, but even if it costs license fees to developers, big whoop. They all pay these for everything already, anyways. Look at Amazon's 1-click patent.
I'm sure that Firefox fanatics will be up in arms, but you know what? Google, Microsoft and Apple all support this. It's not like Firefox is a bunch of broke hippy programmers anymore. Mozilla makes TONS of money. They can pay for this fee easily, or they can stick to their guns and have the only browser out there that doesn't work for video. In but just a few years, this will be the case. They can keep trying to fight the good fight or just get on board and move on.