It's Always Sunny In Philadelphia (FX): I've heard it being referred to as a more obsene, foul, and over-the-top version of Seinfeld. In other words, it hardly ever disappoints.
House (FOX): House is a cranky, pill-popping, selfish doctor, who believes that everyone is a liar, mistreats his bosses and interns, and is (almost) never wrong. What's not to like?
Jersey Shore (MTV): No matter if the cast is in Jersey, Miami or Italy, you can expect to see stupidity and ... stupidity.
Mad Men (AMC): There's really nothing like a show centered around 1960's advertising agency, complete with copious amounts of drinking and curvy secretaries.
The Office / 30 Rock (NBC): The consistently funniest writing on television, hands down. Note that I've never watched Park and Recreation, which I'm sure would make this list.
Top Chef (Bravo): I either can't or choose not to eat 95% of what the contestants cook, but for some reason, I enjoy watching them make weird-sounding, fancy foods.
Lost (ABC): A weird quasi-sci-fi show that will leave you with more questions than answers, with stories presented in flashback and flash-forward format, interwoven with the present action. I don't get what happens half of the time, but neither does anyone else.
Rescue Me (FX): Rescue Me combines serious action, strange hallucinations and dark comedy into an interesting series, but also has far too many uneven and unrealistic story-lines.
The Shield (FX): Vic Mackey is one of the most powerful men alive -- a cop who's not afraid to murder a snitching partner or work with drug dealers to get his way. He's gotten away with murder (and worse) over seven incredible seasons, but will he ever get caught?
The Wire (HBO/BET): Every major publication there is agrees on one thing: it's "the best show on TV." I can't possibly do it justice by explaining why so amazing and why the people who watch it can never get enough.