The video is still there. Sometimes the youtube linky widget doesn't work correctly. If you get a 'video no longer available' message, try this...
If open already, close the window that says 'no longer available'.
Click on the link again.
A youtube video box will pop up with the 'play' icon in the middle.
DO NOT click the 'play' icon or single-click anywhere in the video box.
Instead, DOUBLE-CLICK in the video box.
This will take you to the videos 'channel' page where you can play the video normally.