Also consider that this does MORE than what photo.net's form you gave me does -- as Flickr doesn't have a rigid taxonomy, but a user-defined and very dynamic folksonomy, and they do need to do a full-text search for this.
keep in mind that Flickr gets thousands times
more traffic and number of photos uploaded
Precisely -- Flickr cannot do dumb sorting based on metrics collected from a dumb rating widget so easily, because (a) they are bigger and (b) they have more noise, which follows from (a).
Tell me how to view the highest rated photos for today, current week, current month.
Compare
http://www.flickr.com/explore/interesting/7days/
with, for instance,
http://photo.net/gallery/photocritique/filter (set the filter to "last week")
and you will see how shitty Flickr is. And keep in mind that Flickr gets thousands times more traffic and number of photos uploaded.