April 26 "South Park"—How did they DO that?

Yep. I’m thinking the same thing. The commercials for the episode had a very different flavor from the finished product, which may or may not mean anything. In the ads, it seemed like they were going for kind of a Twilight Zoney feel.
As for the future of SP, check comedycentral.com. They just signed a 3-yr deal, including at least 30 new SP’s and a new series.