Almost all my top picks are already mentioned, except:
Rescue Me (7th and final season coming in September)
And even though it’s only had two seasons, with a third in the works:
Justified
I can’t believe any of you “cocksuckers” haven’t recommended Deadwood yet.
Did that run for 3 or 4 or 5 years? In any case a damn good series.
This posted just reminded me of another one, Absolutely Fabulous.
Another recommendation for Mad Men here. We’re watching the third season now, after having finished Lost and 24. The wife attended graduate school in the US and has been married to me for donkeys’ years, so she’s up on a lot of US history. But I personally remember a lot of the little historical and cultural background details, and it’s always fun explaining what this or that throwaway comment referred to.
We also enjoyed the first season of Glee and are eagerly awaiting the second one to come out on DVD. That would be a quick one to run through.
Dexter has been highly recommended to us, and we’ll probably watch that after Mad Men.
For British series, anything with Steve Coogan and/or Rob Brydon.
Well… Welcome to fucking Deadwood! Can be combative!
I coulda sworn that one was already mentioned. Fuckin’ Wu! Good catch.
ETA: It was just 3 seasons, sadly.
Justified (2 seasons) or Burn notice (currently on season 5)
I’ll also seconds suggestions of Breaking bad, Dexter and Deadwood.
I rewatched some recently with my wife who’d never seen any of it.
It…hasn’t aged well.
-Joe
Deadwood, Rome, Dollhouse, Buffy, Angel and Firefly form Whedon, the Wire.
I liked Due South, too. About a decade old, quaint, sweet series with a very polite Mountie stuck in violent and impolite Chicago.
How about Psych or Monk?
I like several things you like so I will recommend the only recent shows that I have seen in their entirety and not given up on:
The Wire
Friday Night Lights
Rescue Me
Justified (only 2 so far)
Eastbound and Down (only 2 so far)… and not quite a drama
Entourage…also a bit drama free, except for Drama
I just have to add that while we get this question asked nearly every other week, I love them. We always mention the same shows, but there’s always either something new mentioned, or something’s mentioned yet again that I finally cave in and take a look based on everyone’s recommendations. Haven’t seen anything I didn’t like yet.
We are about halfway through season 3 of True Blood and we love it. Season 4 is on TV now but we don’t have cable so we will catch it when it comes out on DVD.
I saw the first season of Justified, and mostly enjoyed it, but never came back for season 2. Maybe I should.
My Name is Earl ran four years and is very, very funny.
Star Trek: The Next Generation and Star Trek: Deep Space Nine, despite a few missteps, were both very strong series. There have been several threads here as to favorite episodes if you want to cherry-pick.
Yes. I am watching Trueblood and have from season 1 in “real time”. This season so far has been very intense and I hope that keeps up. People have suggested Breaking Bad a few times and I have never even heard it so off to Amazon to get the low down. Thanks all. 
Life (only one season)
Torchwood (Dr. Who spin off. Season 4 starting soon)
Farscape (hands down my favorite sci-fi series)
I second the Veronica Mars suggestion though I think it actualy went three seasons
I second Eureka. Light sci-fi romp but the characters are very endearing.
Being Erica is a great show that is filming season 4 right now I think.
I’m a total Castle slut and I think everyone else should be too.
Justified really found it’s legs in the 2nd season. I still really liked season 1, but it was a bit disjointed.
For me, Breaking Bad, Deadwood, and The Wire are the best of the best. I would have a hard time choosing which of those I like more than the others. But Breaking Bad is just the very definition of must-see-TV. The writing and acting in those three are nothing short of spectacular.
Agreed on Farscape and Doctor Who, also give Red Dwarf a try, and even if you’re not a car show fan, watch the original BBC Top Gear series.
The chemistry between Clarkson, Hammond, and May is what makes the show so great, they get just as much amusement bickering amongst themselves as they do behind the wheel of the Supercar of the Week, to say nothing about their challenges
In fact, one of my favorite episodes has nothing to do with cars at all, do a YouTube search for “top gear ground force”…
Oh and the episode where they build a Space Shuttle out of an old Reliant Robin is one of the coolest events in the series
SWMBO started watching Charmed reruns and now I’m hooked on them as well.
Gotta agree on Top Gear, though its not really a series where it helps (or is downright critical) to watch in sequence so it all makes sense unlike most of the other shows mentioned here. I’m not even remotely a fast, expensive, flashy, sexy/macho car guy but I still love the show. You watch those guys doing the show, having a blast, having great adventures, getting well paid and you realize just how unfair the universe can be.
When you say four seasons, do you mean four big, brawny American network seasons, four lean and mean American cable seasons or four British seasons that zip by before you know it? I’d hate for you to be irked if I mention the original Coupling, only for you to find that its four seasons total just a bit more than one American network season.