Last night's episode was very funny, with the boy's reckless heroics and whatnot. The Commish cracked me up.
One of the best aspects of the program is the surrealism of it.. The episode with the 'City Wok' owner's futile attempts to resist the destruction of his wall by 'those shitty Mongolians' is a very good example of this, or even things like in the film, with Conan's dramatically diving out of the building, and that random character turning off his car alarm. Hillarious stuff.
In comparing present episodes, South Park is definately better than The Simpsons, actually being funny. A fine example of this is the comparison between each program's episodes involving boy bands, 'New Kids On The Blecch' against 'Fingerbang'. Fingerbang was much more entertaining and satirical (With The Simpsons hampered by that N-Sync guest appearence, and a rather bad script..)
The only problem with South Park however,, is that due to it's very topical nature, some of the episodes are not going to date particularly well, which to me is a sign of a truly great program, the episodes remaining humourous and relevant across differing contexts. Unfortunately, that J-Lo one may be an example. While entertaining, how will it be to future viewers who may not be as aware of her as we are? Hmm...