I created YouTube test thread in order to see if embedded YouTube video would work for me. Sadly, it does not work.
I have no issues with playing that video in YouTube website but I think YouTube uses HTML5 by default now, therefore the lack of flash add-on is not an issue.
So the question is: Are embedded videos flash dependant? Based on my browser asking me to activate flash, I would say that they are. Is there any chance to change it in the future releases?