My computer automatically upgraded my shockwave flash into that version. Ever since, youtube videos won't play. even videos in other sites. I believe the problem lies in this shockwave flash. i tried updating all that which requires to be updated. But unluckily nothing seemd to be improving. The problem therefore is rooted with this.
I've had the same problem.
This bug is now being addressed by Adobe. For solutions see the announcement at http://forums.adobe.com/community/flashplayer .Their first recommended workaround (regarding RealPlayer) fixed the problem for me. To bad they released this version with this bug ...
Thank you so much! I hope they resolve the problem soon. I badly need youtube now.