[aidenn0]

I (an American) joined a business call with some Germans and when they were speaking in German, they referred to each other as "Herr Müller" and "Frau Schmidt" then since I joined they switched to "Jens" and "Nadin." I just found that to be an interesting cultural difference.

[luckylion]

That stuff is often strange in Germany. It's not uncommon to hear "Frau Müller, kannst Du mal ..." in professional environments where people know each other well ("Du" is informal and usually used with first names, formally it'd be "Frau Müller, können Sie", both is "Mrs Müller, could you" in English).