On August 2nd, 2010, College Humor posted an original video: a parody of Inception written by Dan Gurewitch and David Young. Two days ago, South Park aired a new episode: a parody of Inception that seemed strangely familiar.
See the comparison below.
The last line seems exceptionally blatant, as it makes no sense in the context of this bit.
Update: South Park admitted to the misunderstanding.
This is from the blog of Dan Gurewitch:
David and I just got off the phone with Matt Stone (coolest sentence I've ever written). He was extremely nice and apologetic. He explained that when they couldn't get a copy of an Inception screener, they used our sketch as source material. They thought that the lines in our sketch were taken directly from Inception (and the joke was that they were arranged in rapid succession), rather than original lines written by us.
All is well, and we're going to meet up with Matt and Trey when they're in New York.
[via College Humor]