I had a VERY good laugh, when I read
THIS article. There are so many points I agreed with 100%.
But I guess, I'll always be amazed about (or confused) about the whole "How are you?" deal. I wouldn't ask, if I didn't want to know - so no need to pretend that you are fine, if in fact you aren't. According to everything I've read so far (and the very short contacts with Americans in RL), for English-speaking persons this question is just a question and they don't expect an honest answer.
The fact that really cracked me up was this one though:
Invitations:
[If you say] "Next year around this time, pay a visit to our place..." [to a German person]
Be prepared: The Germans will be there, standing on your doorstep!