Homeland was also very good this year, it managed to keep up the suspense and excellent acting, I'm excited to see the new season next year.
I enjoyed Dexter, I'm not sure I like where they are heading though, it's getting darker and darker by the series. I also enjoyed Castle, I think it's very funny and well written, but perhaps I have a soft spot Nathan Fillion.
Most anticipated TV series for next year is the new Arrested Development. I love the first three seasons, I'm a bit nervous with netflix financing it, I hope the (probably) smaller budget hasn't meant too many compromises in terms of writing and production, but with the excellent cast from the previous seasons all returning, I'm excited to see how they're going to pick up from the end of season 3.
(I must disclose that I haven't seen breaking bad yet, and from what I hear I need to watch it very badly. Especially since I love SOA as much as I do, or so I've heard)
Hell on Wheels surprised me by having a strong second season.
I had high hopes for Copper, but it hasn't really grabbed me in the 1st handful of episodes.
Agree with all the obvious ones:
Homeland, Louie, Newsroom, Sherlock, Game of Thrones, Community.
My wife is addicted to Castle and I've come to really enjoy it too. Since we've caught up to date with that we've now switched over to Person of Interest, which I'm really enjoying.
I've fallen behind with the following and plan to catch up ASAP:
Dexter, Sons of Anarchy, 30 Rock, Breaking Bad.
PS: yeah, I watch a lot of TV :)
If you can get over the fact that it's a kids' show, it's one of the best-crafted series out there. I used to say it was the best animated series I'd ever seen, but now I'd go further and say it was the best show I've ever seen in any genre aimed at any age group. To properly catalog its qualities would take a fairly substantial effort on my part and produce a fairly lengthy piece of writing, so I'll just say this: it's a series that's obviously produced by extremely talented people who deeply care about what they're making, and the more you watch the show the more evident that becomes in a ceaselessly pleasing array of ways. I literally can't endorse it enough.
I also re-watched Oz, The Wire & Seinfeld this year and I'll probably watch them again at some point in 2013..
Oh, and Louie. :)