Ah, you are probably right about the playback. I have both installed - if you say it's XiphQT that enables Safari to use Theora, you're probably right.<p>As for the encoding, I was using ffmpeg2theora 0.25, which according to the release notes bundles libtheora 1.1. Whether or not I'm using it optimally, though, I can't say. I was loosely following the instructions for batch encoding here:<p><a href="http://diveintohtml5.org/video.html" rel="nofollow">http://diveintohtml5.org/video.html</a><p>.. but no matter what I do, the .ogv comes out looking like a poorly encoded DivX.<p>Anyway I'll keep trying, thanks for the correction on the QT plugin.