They need all the help they can get.
It's an interesting problem to tackle. How do you identify the traits of a movie? Genre is the first that comes to mind, but certainly more is required to recommend a movie. Simple classification such as "Comedy" doesn't necessarily mean I will like Superbad if I enjoyed Tenacious D: The Pick of Destiny.
Based on the Netflix website, you can see each movie profile page has several specific categories, or sub-genres. I imagine the current CineMatch system uses these as a tag recommendation algorithm. For example, the page for There Will Be Blood lists these genres:
20th Century Period Pieces
Dramas Based on Classic Literature
Dramas Based on the Book
As you can see, each sub-genre has its own landing page. If two given movies have a similar sub-set of genre tags and I liked one of them, it stands that I might enjoy the other. Let's go back to the image example up top...
|Orange County||BSG: Season 1||Walk Hard|
|Teen Comedies||TV Sci-Fi and Fantasy||Spoofs and Satire|
|--||TV Dramas||Contemporary Movie Musicals|
Other than the "Comedy" link, do YOU see any other similarities? I don't.
OK, what else can movies be related on? What about cast and crew? Ah-HA! Orange County and Walk Hard have the same director and both feature actor Jack Black. Are those truly related criteria, though? Jack Kasdan also directed indie crime thriller Zero Effect. If Jack Black was in Zero Effect, would CineMatch have recommended it, too?
Again, movie recommendation is an interesting problem. I wonder if it could ever work like music recommendation engine Pandora. Check out what I mean by reading this page at How Stuff Works. Could we identify such specific things as plot elements as seen on IMDB.com pages? If I liked a movie with a memorable "peacefully gazing at the night sky" scene, could be there be any recommendation significance to a movie with a similar scene?
Anyone want to go for the million bucks with me? =)
p.s. If anyone can find one single similarity between BSG Season 1 and Walk Hard/OC, please comment!