Is it the way they talked about serious subject matter, while making it funny? Or the neutral space? How about both!

The fact that it made me laugh harder than any other comedy series before or since.

It was just funny. It's too bad that Fox didn't get the humor.

my fave was probably Amy--man was she wicked! LOL
example:

Tommy: Dont think i wasnt listening!! Where is my cat?!
Amy: (with a sly smile on her face) He didnt suffer.


LOL!!!! HAHAHAHAHAH I love that line

For me its just perfect comedy. Not only the jokes are amazing but the way they are acted with physical comedy are outstanding, always finding the funniest point you can possibly think of. And always with little thinks to think about.