Or it could be the best RPG in a long time. Just because it's not fantasy nor scifi don't make it automatically a bad RPG. We will have to wait and see.
(The following is just in general not as a reply to you)
I for one find this project quite intresting, it differs from the normal fantasy & scifi rpgs by the setting alone, not to mention the humour that comes along with South Park. You don't have that much humour in rpgs. I don't think I've really laughed at all while playing most rpgs, only Alpha Protocol and Old World Blues had dialogue that actually made me laugh out loud multiple times.
Not to mention this just adds some diversity to Obsidian's catalogue. 2 x fantasy (+ expansions), 1 post-apo (+ expansions), 1 scifi, 1 "real world" spygame and now a "real world" game based on a animated show. You really don't see that from the "competition". Bethesda is busy dishing out Elder Scroll and Fallout games, BioWare (Edmonton) seems to be stuck (for the time being) with Mass Effect and Dragon Age games and the Polish have their Witcher series. And yes, those series are all well received and are selling well, but still I don't think we can expect anything new and/or different from those companies any time soon just sequels...