Mozilla has had real power for a brief period, when both MS and Google had their eyes off the ball. Once Chrome matured, the game was up. It didn't help that it took them ages to fix widespread performance problems in FF...
This said, if they go back to their roots as "ayatollah of open web and open source", I might consider them again; but until they're just another ad-backed bureaucracy, I might as well stick to a better one.
Mozilla was never "ayatollah of open web and open source". If it has been, firefox would have never been available on Windows, like some people at the time argued.
Google did well technically on Chrome, but investing a huge amount of marketing dollars (like bundling chrome with other nice things like toolbars) didn't hurt them.
Mozilla still has some power, but they don't think they have enough to mount a lone assault on video DRM. I'm inclined to agree with them.
But I'd rather they saved that power for the next fight rather than going kamikaze on this. I'm sure there will be a next fight, and there's a good chance that it will be something smaller, or they'll have another major browser on their side.
This said, if they go back to their roots as "ayatollah of open web and open source", I might consider them again; but until they're just another ad-backed bureaucracy, I might as well stick to a better one.