Frasier, one of my favourite comedy shows ever has a laugh track. I also like Peep Show and Scrubs though, and they don't have a laugh track. I like Friends and that has a laugh track.
Basically I don't care eitherway, you can get good and bad shows with and without it.

The only time I really ever noticed a laugh track on a show is with the terrible and unfunny show Everybody Loves Raymond. The laughter on that comes at every single second and lasts for about 20 seconds each joke.