Squealing - is it the tensioner?

[fiasco]

I started getting a loud, high-pitched squeal today. Sounds like it is coming from the top side - i.e. not down by the alternator but somewhere from the tensioner or higher.

Link to video.
http://youtu.be/LT5zRmxozrQ

Does this sound like a tensioner bearing gone bad, or a timing belt pulley, or maybe the belt itself? Should I expect to resolve this with a timing belt and tensioner change, or do I need to be prepared for something bigger?

Thanks,
-- se

[fiatfactory]

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