Back when I worked at the big Y! Flickr was treated largely with kid gloves, you had a passionate photography community who viewed Yahoo! at best with indifference, if not outright hostility.
So it was interesting to notice that Yahoo! now has a branded top bar on many flickr pages.
Secondly, from a context point-of-view, given the difference in Flickr users compared to Yahoo!’s other branded pages I can’t imagine a context where this bar will be producing too much cross-network traffic. But you never know it may surprise me.