In that vein many of you have explored and used MacTubes, which is a delightful tool for direct playback of YouTube videos. It's kept up to date with Google's frequent screwings around on the backend, it has a variety of playback methods including Flash, WebKit and QuickTime, and it's probably the highest performance way to play YouTube videos on a Power Mac (even HD is possible with sufficient grunt). I downloaded the source to play with and discovered it can be fed a URL through Launch Services, so I tried that, and it worked -- it figured out the video location and automatically started playing it.
The MTE also has a trick that the QTE doesn't yet: you can direct it to start playing in MacTubes and close the tab in one step. One big irritation involving the QTE, and with YouTube in particular, is that YouTube will start streaming the WebM video while the QTE is trying to load the H.264 version at the same time (this can be bad enough on a slow link to make QuickTime think there's no data and give up). There used to be browser addons that would defeat YouTube's autoplay feature, but none of them work anymore and Google seems to be trying to bust these techniques also, thus this feature (that will always work): now the full bandwidth is devoted to streaming the video through MacTubes. If people like this feature, I'll add it to the QTE. (Another idea might be to back up to the previous page, or if there is none, then close it. What do you think?)
The MTE does not replace the QTE (and, for that matter, the MTE is completely independent of the QTE; you can have both of them installed simultaneously, even): you'll still need the QTE to play non-YouTube HTML5 video, which MacTubes doesn't handle, and if MacTubes becomes unsupported one day we'll still need QuickTime. (However, I'm able to build MacTubes from source on my G5 independently, so that's a solveable problem if its author someday decides to hang up his hat.) I'm also not planning to merge the MTE and the QTE for the foreseeable future because it's nice to have a playback alternative, and saving video and getting to HD formats is a little easier in QuickTime Player.
Consider the MTE a beta and give it a spin. Download it from its wiki page. The MTE requires TenFourFox 24. Test it out on Jean-Claude Van Damme injuring himself, or maybe some of MTV's finest cartoons when they actually played music.
17.0.11 is live. I'm going to make one tiny change to garbage collection scheduling to help intermittent stalls prior to release of 24.2.0, which should be the first public release. It looks like we will have a mostly full set of langpacks, too, so a "great work, guys" to Chris and all the localizers.