[TYPO3] Collaborative Filtering

[Ellison, Todd]

I would like to do some collaborative filtering (like
http://www.vogoo-api.com/) on a site we are working on.  Basically, I
would like users to be able to rate content items, compare their ratings
to other users, and suggest content to them based on those ratings.
First, is there an extension to do something like this that I am
missing? I would hate to re-do work someone else has probably already
done better.  Second, do you guys feel that this would be something
terribly difficult for someone who has lots of PHP experience, but has
never developed a Typo3 extension before, to implement?
 
Thanks for your help.
 
Todd