I know the big games from the Star Wars line (KotOR 1 & 2, The Old Republic) and all their associated novels are generally considered by Lucas to carry higher canon than most other things because of sheer exposure and because of their impact on the franchise (exploring a time he never really touched on). For instance, there was a time when Darth Revan was going to make an appearance on the Clone Wars show in an episode about Anakin learning about former Darkside masters. Revan also got an action figure at one point (and it's still going for a decent price), as well as Darth Nihlus.What? No. Movies beat everything and the TV show beats everything else, yes, but after that, everything else is pretty much equal. Unless it's been retconed or otherwise declared non-canon (the What If comics for example). The form of media for C-canon material (which is "all recent works (and many older works) released under the name of Star Wars: books, comics, games, cartoons, non-theatrical films, and more") has nothing to do with canon precedence.
Shadows of the Empire is also generally considered canon, despite taking place during the original movies, because it's events really don't change how the movies play out. It got a comic and toy series as well, including recent reprints of the comics included with special themed action figures a while back.