As confusing as this may sound, when I 'like' a page on Facebook, I do so because I like what the page is about. If you were to look at my Facebook profile, you'd get a pretty good idea of my personality. My music tastes are the most complete section, where all the artists I like in real life are listed there - no more, no less.
When it comes to television, I tend to hold off on liking the Facebook page for it until I am caught up with watching it, so that not only do I avoid spoilers from the page itself, but that nobody else talks to me about it until I know as much about it as possible. Sad? Yes. Phoney? Yes. Sensible? Yes. It's a calculated move that simply ensures I don't have spoilers or questions sprung on me about a show I don't entirely know.
With films on Facebook, I simply can't be asked. I use the website Trakt to keep track of all my television and film watching, which is enough for me. If people really care about what I watch, they can check on there. Adding the, at the time of writing this, 555 films that I have seen in my lifetime to Facebook would take an inordinately long time.
The amount of 'fun' pages I like on Facebook amounts to two - "Hey, batter batter batter, swing batter!" (a phrase used in Ferris Bueller's Day Off), and "Things Bishops Boys Don't Say" (a page that posts inside jokes about a school I attended). I don't like pages with jokes, or expensive car wrecks, or ones that post things completely unrelated to the title of the page, because I like to keep my online presence in the eyes of both onlookers and myself as clear and representative as possible.