Yeah, learn some German bitte!

Germans usually speak English (especially in Berlin), but if you speak some words German you show you try and care. Signs etcetera are always in German.

Standard European plugs, you can get a American -> Europe converter for a few EUR. I ordered mine at eBay, 2 for 5 EUR incl S&H (cause I bought some American electronic devices while in America).

Be sure to grab some Club-Mate at C-Base. Its the German hacker drink. C-Base is pretty cool anyway.

American beer is pretty bad, so some German beer is also recommended, but I don't know much about brands, I'm more into Belgian and Dutch beer. Mind you, any beer you drink in US with EU brand is import quality. The Heineken in US tastes different than the Heineken in NL.

I find food in Germany always decent with good service, for a sane price, in contrast to my own country. I know some good restaurants, but not really 'German' style, and IMO if you are in a country you should experience their culture.

Night life in Berlin is 24/7 alive!