oldtimes, I forgot to post this earlier.
What you posted is the html5 beta that youtube has setup. It doesn't work with half the videos, because youtube doesn't want to part with their ads.
I'm happy to say I just uninstalled flash. It's gone for good, and I already feel "cleaner".
After being kind of disappointed that the youtube5 extension wasn't available for Google Chrome (or so I thought), I ended up porting youtube5 to Google Chrome.
Of course, after learning the specifics of writing Chrome extensions and taking the time to write a Google Chrome version of Youtube5, I suddenly see a YT5 extension on Chrome's extension site. Oh well, it was worth it anyway. =)
Feels good to be flash free.