The humour that has been described seems to have moved on from the old fashioned Irish immigrant or Polish immigrant joke to more of a joke between equals, where the group who are the butt of that type of joke are more resiliant. The New Zealand/Australia joke actually makes a joke of the rivalry/jealousy/hatred(I don't think so?) that exists between the two countries, rather than saying "all people from ... are stupid which is what the older, less sophisticated jokes said (and still do). A JAP can't really help the way she is (and I adored the very self-aware ones I met in NY), at least some of the people mentioned in blonde jokes have a choice over their hair colour (my friend wears a t-shirt that says "speak slowly, natural blonde").

The main form of humour amongst those who used to be called alternative comics is observational humour - telling a story about something that happened to you (where the joke is largely against yourself), a strange experience, a sudden realisation or trying to make sense of politics or big business (anyone who actively seeks media attention to promote their business or political cause is considered fair game, discussion of behaviour is fair game, discussion of physical attributes or anything that a person is not able to change (eg race, gender) is not).

I’ve been looking for a theory of humour (and posted this before), based on a discussion that I had with a friend who came from from a hugely successful comic’s family (his father was known for combining magic and clowning) and was trying to establish himself as a comedian. He had three main categories, which I think incorporated the following:

Types of humour:
Jokes
Often brief story with a punchline. Can be a humorous one-liners.
Funny Situations
Two or more elements that are combined that show contrast, like a fish out of water or two or more elements that are alike.
Funny Words
Puns.
Spoonerism
Transposition beginning letters of words and changing forms.
Exaggerations
Blown up stories.
Repetitions
Repetition of situations or words that seem unrelated 'til the punchline brings them together.
http://www.laughter.com/comedians/comedy.html
plus his theory of threes which spans a few of the categories shown, where the third thing mentioned (or repeated) gets a laugh.


So here is my entry for the $50 prize (save it until 1/1 and you can send it in Euros, for my travels):

"Doctor, I can't stop behaving like a dog."
"How long have you been acting this way?"
"Since I was a puppy!"