I agree wholeheartedly about 30 Rock. It is one of the few television shows anymore that can make me laugh. But I guess really that's always been the case. Can anyone really remember a time when there were more than just a few great comedies on television at the same time? 30 Rock is the perfect mix of believability and relatedness alongside downright silliness and complete characters. Dr. Spaceman is one of my favorites.

Curb your Enthusiasm is worth mentioning as another great comedic force on television today. It is the perfect evolutionary jump for Larry David from Seinfeld. Put simply, it's a show about a neurotic New Yorker in the most foreign environment that exists, LA. It's an innovative mixture of improv and script. For every episode Larry David writes a minimal outline with almost no dialogue, then the cast runs through two rehearsals where they improvise everything inside and then no matter what, they take on the third try.

I'm excited to see the next good comedy emerge on network television. Most of the critical comedies went away when HBO and Shotime came along and allowed for continual cursing leaving a huge gap on all the old channels. In America at least, 30 Rock is running unchallenged for comedic dominance on the regular stations as most of the big forces out there like Ricky Gervais are moving their projects to the premium stations.

Actually though, as I think about it more, there are a number of great comedies on network television, ha. But they are all completely different which I guess is why I didn't think of them right away. The Daily Show with Jon Stewart, The Colbert Report, and South Park are all truly great. I snubbed South Park for the longest time as bottom of the barrel humor, but really it's some of the most spot on satire out there today. Almost every show directly hits on and laughs at crucially contemporary things. Last season the episode about the Jonas Brothers came equipped with a 200 story-tall Micky Mouse crushing cities as he sells sex to little children.

The great thing about comedy is that there will never be a time when the great stuff isn't on the market.   

I love the Ricky Gervais Show the podcast. I often listen to it when I'm on the street and have to stifle my laughter so people won't think I'm insane. The show is an eternal conversation between Ricky Gervais and Steven Merchant, the creators and writers of The Office and Extras, and their friend Karl Pilkington. You learn very quickly that the show is really about Karl and his eccentrics. The whole concept is the other two laughing at their numbskull friend with a very round head talk about evolution and time travel.
One of my favorite segments on the show is when they read excerpts from Karl's daily diary (I wish he would come write on THINQon)  

here is a good entry:

I'd be worried that an alien could read my mind. I had that problem once years ago when I worked in a studio making cassettes. Some mind reading woman was having some cassettes made, she waited while I did them. She had a small dog. I knew she was trying to read my mind so I just thought about the dog. I thought that would confuse her because she wouldn't understand why I was thinking about her dog.

The next 5 minutes are spent with Ricky and Steven trying to get into the innerworkings of Karl's mind when he wrote that down.

I love 30 Rock! I would definitely agree that it is one of the best shows on today (possibly ever), along with most of the others you mentioned- The Office, Colbert Report, South Park, and, of course, The Daily Show. I only started watching 30 Rock last season, and was ecstatic when they got an Emmy (at least until I remembered that even Emmy mentions can't always save a show- see Arrested Development, which I really miss. Wish it had caught on more with the general public.) Never seen Ricky Gervais or Curb Your Enthusiasm- will probably check them out at some point, though. It's really great to hear that people actually appreciate intelligent satire- I was pretty close to despairing over the fate of humanity a few days ago, but then Jon Stewart came on :).