It has finally been confirmed that Flickr has been bought by Yahoo!, after a month or so of endless speculation. Caterina confirms this on the Flickr blog today.
The interesting part of this new relationship is that Flickr features Google AdSense ads on their site. It will be interesting to see if Flickr becomes a beta test site for the new Yahoo Publisher Network (YPN), as it would obviously not make sense for a Yahoo! owned property to continue running Google AdSense ads when they have their own competitive program available.