just realized this today as well. The video player is a complete disaster, even with forced h264 extension.
EDIT : this is really really weird. I'm pretty sure youtube played perfectly fine yesterday on firefox (mac os x here too). Call me paranoid, but could it be possible that they altered something to have the video stutter on firefox in the meantime ??
EDIT : this is really really weird. I'm pretty sure youtube played perfectly fine yesterday on firefox (mac os x here too). Call me paranoid, but could it be possible that they altered something to have the video stutter on firefox in the meantime ??