Right now - Game of Thrones. It's intelligent, complex and realistic (which is odd to say for a Fantasy). 

Have you read the books? They are awesome.

Mine are Shameless (Showtime), Game of Thrones (HBO), and American Horror Story (FX).  Shameless (the U.S. version) just finished its 2nd season. It's pretty dark but comedic.  

Looking forward to season 2 of American Horror Story to see how the story line goes with the new family

Yeah. Agree.

I also quite like Suits, though the 2nd series is already less interesting and I can't see it picking up.

Doctor Who, because stories are fun and I just love the doctor.

It's also interesting to see how the series progress though years and actors....

DW  actually brought me back to the English language... and got me interested by the UK

yeah, I'm a Whovian  

I'm currently watchinh Heroes, Californication and Game of Thrones. They are all good in different ways. I also finished recently Sherlock (the series) and thought it was brilliant.

I'm a loyal fan of Glenn Close and love her role as a lawyer on Damages. Each season is a case to be resolved - a very twisted one - so you're hooked to the whole season if you wanna know how the case is resolved :-) The episodes are quite catchy and the cast is brilliant. The 5th and final season begins this week. They're killing the show unfortunately as it's not as profitable as the TV series for teenagers :-
    

http://youtu.be/zZuxSi679jg

Recenntly watched the following 

Rome (HBO) - 2 series of 10 episodes each.. intelligent look at Ceasars battle with Mark Anthony. Lots of sword fighting, nudity and swearing, intruige and politics etc.

Spartacus (HBO) - Blood soaked gladiator series (2 x10 episodes) with gratuitous nudity and swearing following the slave uprising in the Roman empire.

Band of Brothers (HBO) - WW2 drama following a group of US parachute soldiers fighting in France and Germany. Well made and based on true events.

Game of Thrones (2x 10 episodes so far / season 3 in the making due out next spring) - as above..brilliant.

Californication---- needs no comments.

I agree i loved Damage (so nasty and clever) !! can wait for the final one

agree also i love Sherlock ( i am in love with this guy so clever) I watched Heroes and Californication but stoped ( Californication is too much always the same...and heroes i felt a little bored) but still they are good series.. i am waiting for brand new one :-)

No one for 'female series' ?? i loved Brothers & Sisters, Army's wife - ahahahha I am a romantic but i assume  so ladies please share as well...

i definitevely should watch Game of Thrones ! it looks great and shameless seems also very interesting !! thanks :-)

Is Dr. House too old school for this crowd? :)

The correct name would be House M.D.

Breaking Bad was a very good series, Malcolm in the Middle's dad in a slightly different role as a Chemistry teacher moving into producing top notch crystal meth to make money.  A great series, gritty, black comedy/drama, fantastic characters, highly recommended.

If you're after female leads you might like Revenge. I started watching it a short while ago and was easily hooked. 

The first couple of seasons of House MD were great, but I think they ran out of steam around season 4-5. 

Good Wife, The Closer and Homeland

The Killing I and II -- original Danish version, crime drama and lots of knit sweaters;

Mad Men -- 1950s/60s -- Madison Avenue advertising execs. Dapper Don Draper..

The Sopranos -- ganstas, therapists and housewives who bake zitti;

True Blood -- southern US weird gothic vampires, fairies, et al;

The Wire -- 6 seasons of drama about US east coast city Baltimore, MD -- how corruption and drug trade affects many facets of society including youngsters, business, politics and police.

So many great series especially from Home Box Office channel in the States. Looking forward to Game of Thrones...

hells kitchen is an amazing show but also happy endings is a very entertaining one. 

this never gets old.

http://www.youtube.com/watch?v=qIWVJI4uQl8&feature=related

Hi. I like The Big Bang Theory, 2 Broke Girls, Modern Family because they're witty and funny. I also watch How I Met Your Mother, because it was funny the first few seasons and I'm kind of following the story even if it's not that funny anymore. I like Glee for their music/songs. And The New Girl is growing on me. I'm looking for new series too since all those I mentioned will only be back on Sept

What season is Heroes now? I was addicted to Heroes before, but then the plot got too complicated for me.

I'm watching it from the beginning, I am at season 2 now.

Ah. I thought it was still on. I think I got to first half of season 3. Enjoy

Watch the British series Downton Abbey.

No they stopped in 2009 after season 4.

I like New Girl because it's crazy

But if I had to pick one, it would be Mad Men.

Criminal minds, the Mentalist, , NCIS, Castle... All that has to do with criminal stuff and psychology.

I recently watched Sex and the City, Season 1 (Thanks Izzie!) and I enjoyed American wives (or Army's wifes?).

One serie I really got addicted to while I was in the States was Alias. This was awesome. JJ Abrams has such an amazing mind... I still keep in mind this phrase from Sidney Bristow, alias Jennifer Garner: "You're cute... But I'll pass."

I'm sure I'm forgetting series.... But that's what I can think of right now.

Thanks to all, very nice to have all these answers

Futurama - because the future is full of win and other things (animated)

The Sopranos, my number one, unfortunately I can't help cursing like them after watching two in a row.

Old but the best comedy for me, Seinfield.