I am German, been in the US since the late 90's and I can confirm that there are quite a few significant cultural differences, verbal communication included. I have also been working for the same company since I arrived here and so the people in my direct work environment are by now used to that I don't monkey around when I talk to them. Still results in some raised eyebrows when we are in meetings with strangers and they settle in for a comfortable all morning meeting and I open the meeting with something like "Alright gentlemen, thanks for being on time, let's not screw around and get right to the bottom of why we are here today. I have another engagement in an hour and would like to leave here with the matter resolved."
Fun stuff.
I also think that Germans as a people lack the level of empathy found in some other cultures. The closest I can compare it to is that Germans are more like Republicans in the US thinking that life is what you make it and you are responsible for your own actions and the choices you made. You have all the opportunity you need to succeed in life and if you don't then there's no one to blame but you. That tends to not be a very popular view in a society that blames everything and everyone else for one's predicament(s).
Lastly: Ein echter Deutscher wärmt sich am Eisblock! which translates to "A true German finds warmth in an iceblock" or some such. I'll leave it up to you whether you want to interpret that as us having such cold hearts that even ice can warm us or whether we are so crafty/hardy that the worst of situations can't really put a dent into our resolve.