Truth be told, I really don't watch much TV. The only show I make a point of watching is "Castle", and I watch that on Hulu because it comes on after my bedtime. I watch nearly all of my TV on the computer. I do enjoy "Endgame", which is a Hulu exclusive, I think. Occasionally I watch the new BBC version of "Sherlock"(on Netflix), and I do enjoy some British Comedies (such as the Vicar of Dibley special!), but I think one of the shows I have enjoyed the very most was called "Jam & Jerusalem" in England, and "Clatterford" in the US.
I really love well written ensemble shows--it is sad that there are so few of them.
Speaking of which, if you haven't watched "Firefly"--drop whatever you are doing right now, and go watch it--immediately! As of this typing, it is on Netflix Instant View. Sadly, there are only 14 episodes, so it doesn't take all that long to catch up on!
I do enjoy webcasts because they are short, so I don't have a major time commitment into them.
I haven't started watching "Dr. Who" (even though David Tennant is just delish!) or "Downton Abbey", because I just don't have that much time--I waste enough as it is! However--they are at the top of my "things to watch when I have a badly broken leg" list!