Good job. For a long time I used another script to replace flash-videos with my generic player. Since "Youtube without Flash auto" dows not work for me anymore I tried this one.
I like that it worked out of the box.
It would be fine if one could alter the default quality of videos played. If I alter the variable gVdoDefault to "High Definition MP4" it's fine, but there's no fallback if there is no video of that type.
Maybe you could include a test if the video is accessable and else load the next best quality available.
With "Youtube without Flash auto" you could set the options from within the browser via some external file. Have a look at it.
And the controls could easily look nicer ;)
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