Actually Greg, You aren't the first person to have struck this. I remember with the penultimate update that came from Adobe, YouTube stopped working here. Unfortunately, I cannot for the life of me remember what on earth I did to get it working again. I seem to remember looking at the help pages on YouTube itself, if that is any help at all.
I’m wondering if maybe they had an issue and fixed it because I got two Adobe Flash auto updates at startup, two days in a row. That's seems unusual for Flash updates to come so close together like that.
I reloaded it and the second time it worked. I guess they sent me a corrupted file ... or it was a FireFox problem. On the second pass I uninstalled everything Adobe including the FF plug ins.
That gives you the new one that doesn't work. I managed to find their archive page and get the previous version but they make you dance a lot to actually get it installed. I imagine they will try to upgrade it pretty soon. I wonder if this is because I am still running XP