YouTube's site is down for either new features or maintenance of some kinda. I browsed to the site this evening and saw the following page:
Update #1 - After 2+ hours, still no YouTube. I got tired and went to bed.
Update #2- This morning YouTube was available. No new features that I could find. I guess they were just doing maintenance. Nothing exciting here. :-(
I find it interesting to see how many of the currently popular sites today are not able to maintain high availability. At MSN and Amazon, we had mechanisms in place to roll out changes/updates without taking the service down.