I can't stand Friends, I've tried to watch it and enjoy it, but it's like disposable pop music to me, just mindless, silly humour that doesn't require any thought. I must admit I have found Joey and Chandler to be sometimes funny though.
Overall it reminds of the Simpsons episode where Mr Burns takes over all the tv stations and has his own shows with programmed laughter, because it seems like the audience laughter on Friends is like someone pushing a button.
Anyway, Seinfeld on the other hand, while sometimes a little bit silly, is brilliant. All the characters, while lovable are all very selfish and self-centred, which is a little scary considering how many people can relate to the show. Maybe we're all selfish and self-centred too.