It's not park the car in the harvard yard, it's Pak the cah in the hahvad yahd =P Or something like that, they don't pronounce R's.
I think it's odd that some of you think that the NYC accent is the most indicitive of Americans because it actually is only a small sector of the states. If you watch American TV shows there is an obvious neutral American accent that most people tend to have, maybe with some slight variation.
I'm told I have a slight southern accent (from Maryland). My mom and dad say "Sundy and Mundy" instead of "MondDAY" if the word is at the end of a sentence, and my mom says "warsh" for wash. My dad says "woosh" for wash. And I say "wahsh" for wash (which is, i believe, the correct pronunciation).
I really dislike when people say "melk" for milk, "wooter" or "wuter" for water, and "pellow" for pillow!! Not really, but it's a little pet peeve =D