Tags sorted by TopRatedPopular

Speaking of tag sorting, what is "Top-Rated Popular" supposed to mean?
My guess is that "Popular", here, refers to tag popularity. What is the cut-off?
I am asking because I am getting some weird results.

www.listal.com/movies/based+on+a+book/top-ratedpopular
Page not found
We could not find the page you requested


www.listal.com/actors/tv+guest+star/top-ratedpopular
Page not found
We could not find the page you requested


www.listal.com/tvshows/soap+opera/top-ratedpopular
3 results


www.listal.com/tvshows/science+fiction/top-ratedpopular
includes
www.listal.com/tv/adventures-jimmy-neutron-boy-genius
Science Fiction (4),
rating 5.6

but not
www.listal.com/tv/sliders
Science Fiction (4),
rating 6.7

Update lag?