My ten favourites are in no particular order, except perhaps for Bilko(made late fifties and still brilliant)
The Phil Silvers Show - Bilko
Roseanne
M*A*S*H
Happy Days
Seinfeld
Taxi
The Simpsons
Bewitched (I have fond childhood memories, right!)
Cybil
Curb Your Enthusiasm (But haven't seen 'em all)
Quote: Griff @ February 14 2011, 6:17 PM GMTIndeed.
And in no particular order...
Frasier.
Curb Your Enthusiasm.
Modern Family.
30 Rock.
Friends.
The Office (An American Workplace)
The Simpsons
South Park
Futurama.
My Name Is Earl.Bubbling under:
Seinfeld
Roseanne.
Married With Children.
MASH.
Taxi.
The Addams Family
Top Cat
Looking at that list, I'm surprised that I don't see Arrested Development in there!
1)Seinfeld
2)The Simpsons
3)Curb Your Enthusiasm
4)30 Rock
5)The Office (if I were on a Desert Island Disc type show I'd take the American over the UK Office to my island)
6)South Park
7)Night Court (this is prob' because when I was a kid I worshiped the show)
8)The Honeymooners
9)The Larry Sanders Show
10)It's Always Sunny/Louie/The League - Trio of current FX comedies all tied for 10th!
There's tons of shows that could make my list on a whim... Son of the Beach, I Love Lucy, Barney Miller, All in the Family, The Jeffersons, Married... With Children, Cosby, Cheers, Frasier, My Three Sons, Mr. Ed, Taxi, Phil Silvers, Three's Company, Car 54 Where Are You?, Andy Griffith Show, Get Smart, The Odd Couple, Family Ties, The Dick Van Dyke Show, MASH.
Quote: Griff @ February 15 2011, 10:23 AM GMTI'm one of these weirdos who doesn't like it. I have the box set and everything and after about three episodes I gave up.
Huh, it's the best sitcom of the last decade for me; and by quite some way, too.
Quote: Griff @ February 14 2011, 6:17 PM GMTMy Name Is Earl.
Loved the first series, but it seemed to get progressively worse after that. Third season was awful. Haven't seen the fourth one yet. Plus, aren't they all scientologists and it was actually a subliminal recruitment tool?
Quote: Matthew Stott @ February 14 2011, 6:33 PM GMTLooking at that list, I'm surprised that I don't see Arrested Development in there!
Or Larry Sanders. I know Griff hasn't seen it but I expected on my urging he'd have rushed out and bought it and watched it that day.
Quote: chipolata @ February 15 2011, 1:36 PM GMTOr Larry Sanders. I know Griff hasn't seen it but I expected on my urging he'd have rushed out and bought it and watched it that day.
I just got through with season one, first time I've ever watched the show. Enjoyed it, Hank is awesome, but surprised by how little seems to actually be going on each episode! I suppose I've become used to the more story packed style of American sitcoms recently.
In no particular order....
The Larry Sanders Show
Dream On
Third Rock from the Sun
Curb your Enthusiasm
Frasier
Seinfeld
Arrested Development
Taxi
Cheers
Police Squad
Also not in order:
Bilko
Jack Benny Show - really sketches with the same characters each week and he'd have guests over to his house to rehearse as an excuse for performances.
Mary Tyler Moore Show
Dick Van Dyke Show
Rhoda
The Honeymooners
Taxi
Newhart
Cheers
Frasier
Benson - the butler from Soap
*The Jeffersons
*Maud
*But oddly not All in the Family
Alice - by some of the All in the Family writers, too.
Golden Girls
Empty Nest - they made the pilot on the Golden Girls' set.
Get Smart - the most quotable lines.
The Lucy Show - when Milt Josefsberg, Garry Marshall & Jerry Belson were writing.
Seinfeld
Happy Days - early series
Laverne and Shirley
Larry Sanders
My Two Dads - Especially an ep where the two dads are after the same girl. Reiser goes to her office to help her decide and it turns out she's studying them for a psychology exam. At which point Evigan bursts in in tight pants, ruffled shirt with a Mexican Marimba Band and mimes to Jay and the Americans 'Cara Mia.'
The Odd Couple - again Garry Marshall
Is that 10?
Oh and Friends. For me the difference is the punch-up guy. They go home when the show is funny; we go home when the unions are finished.
A rough top ten off the top of my head, in a rough order.
Seinfeld
Arrested Development
NewsRadio
Community
It's Gary Shandling's Show
Party Down
Parks & Recreation
The Office
Home Movies
Night Court
1) How I met your mother (best exposition in TV - suit up!)
2) Boy meets world (for somethingthat's a kids show it's great)
3) Friends (got to be great e4 has 100year deal with it)
4) Entourage (sitcom? has situation and comedy in my defence)
5) Seinfeld (not that there's anything wrong with that)
6) Family guy (basically a sketch show sometimes but still good)
7) The Simpsons (Doh!)
8) That 70's show (I even forgive it for launching Ashton Kutcher)
9) Spin City (With J Fox)
and Drum roll please
10) Scrubs (even like the the new ones)
Discuss
Actually watching "The Nanny" right now - I don't mind it - I don't mind it at all. 
INPO(In No Particular Order)
Curb Your Enthusiasm
MASH
The Office-An American Workplace
Seinfeld
Perfect Strangers
The Odd Couple
Friends
The Naked Truth
I know its not 10 but close 
Big Bang Theory
Married with Children
cheers
Taxi
Golden Girls
The Simpsons
Roseanne
Phil Silvers Show
S'all I gotz
Has to be
1. Roseanne
2. Friends
3. Ellen
4. Frasier
5. Cybill
6. 3rd Rock From The Sun
7. Caroline In The City
8. Mork and Mindy
9. Little Britain USA - It counts!!!!
10. Cheers
Actual List:
1.Arrested Development
2.Curb Your Enthusiasm
3.Flight of the Concords
4.30rock
5.Entourage
6.The Office
7.Parks & Recreation
8.The Simpsons
9.How I Met Your Mother
10.American Dad
Alternative List:
1.Family Guy
2.The Ricky Gervais Show(technically american)
3.The Sarah Silverman Program
4.Futurama
5.Community
6.Fraiser
7.Modern Family
8.Scrubs(apart from the last 2 series)
9.Bored to Death
10.South Park