South Park is made in 6 days time. Every episode is done in real-time, as in, right now as we speak they are writing the story to the next episode and doing the full animation/show. They made the Obama/Cain episode in 24 hours. That's why sometimes an episode kinda sucks, or isn't as good as the previous one, or you'll have 3 average episodes then one hilarious one, because they literally make an entire episode from story to animation in 6 days, you never know what you're gonna' get and neither do they until half way through the week.
Didn't know that. Pretty neat.