Number 52
I wrote a full review for the Kill All Monsters! blog, but the short version is that Skyline had no story. It was an idea for a story, but it went nowhere and ended at what should have been the movie's halfway point. Horrible.
Number 51
The movie that proved that M Night Shyamalan is so far gone that he doesn't even have to direct the movie for it to suck. Devil didn't make any sense and replaced Plot and Character Motivation with things like Fate and Whatever Shyamalan Decided to Pull Out of His Butt.