There are three known and confirmed bugs with YouTube. They include not being able to save changes being made to videos, and issues playing and sharing videos in YouTube Groups and Orkut. Here are the three threads created by Liz from the YouTube team:
(1) Known Issue: “Save changes” button doesn’t appear on “Edit video” page:
(2) Known Issue: bug playing videos in YouTube Groups:
(3) Known Issue: issues with YouTube videos on Orkut:
So those are the three issues.