That episode seemed a little weak at first, but I've found myself chuckling at every episode of CSI and it's progeny I've seen since. Especially last night's CSI: NY, when Sinise and Kanakaredes were rubbing Sinise's hands with ink. grabbing all those wigs, and shaking their heads. It was almost as much of a parody, albeit unintentional, as SP's cop staring at all the hand mockups and hand websites, and his own friggen hand.
Plus, like most South Park episodes, the serial killer episode was paroding a similar murder that has recently happened in Colorado. A woman was found dead with her hands missing. Gruesome, but from what I know they haven't found any suspects. It is kind of like the Casa Bonita episode with a lot of local references and the freeway to the indian casinos. Matt and Trey do keep their eye on what is happening in their home state.