What makes this show great is that every single character is a true a-hole. There are no sympathetic characters and none are presented as such.
It's the complete opposite from a bonehead show like Lost. On Lost, they tried to make EVERYONE a sympathetic character by making the characters appeal to a certain demographic through societal stereotypes. On this show, 99.999% of people watch and think, "I could never be that person." And that's why it works so well.
On the comedy side, it's the same as Seinfeld. They were are annoying people that you rooted against. And it's what made it great.
-chef