I was in Berlin for a couple of nights in November. I didn't make it to Casino but I did have a good time in a place called Sage. It had a bunch of different areas with different atmospheres and different music: pop house, funky house, techno/electro-house, lounge, and R&B. The electro-house/techno room was playing the best music that night, and I'm more into straight-up house.
My second night I took the easy option (I was in town alone) and went to see Faithless in concert at a movie theater-turned-club near the airport (the one that's in the middle of town). Really great show... probably enhanced by the amount of alcohol consumed.
I found the city to be really civilized. The subway/elevated rail system run 24 hrs on weekends and they're a much better way to get around. Clean, safe, and very efficient.
Better restaurants in the West (Charlottenburg) and shopping in the East (Mitte). Most of the interesting clubs seem to be in Friedrichshain, also in the East.