I'll second Community.
As for the worst, The obvious champion is still the long reigning MTV and VH1, it'll take a lot for someone to top them in the category of terrible stupid people driven TV, but they do have some aspiring competitors - The History Channels, The Discovery Channel or TLC. With similar story-lines as well, stations that started off with quality ideas and programing and now show stuff that is holy unrecognizable to what they once were. I get embarrassed about how awful their programing has become.
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?It's a sad thing not to have friends, but it is even sadder not to have enemies.? - El Che