For example (these are just examples, not my real points):
"I like how free, friendly, approachable and easy to talk to Americans are."
"It annoys me how loud and obnoxious Americans can be."
Tell all. You can let the most outrageous stereotypes run free, it is a safe space for them here.
PS: Americans are welcome to pitch in too (just mention that you are one please).
PPS: I'll keep this post at the top of the front page for a couple of hours to get more people to contribute, I do not have enough people on my friend list for a proper "bitch fest".