I managed to spend some time this evening with the EOS 60D shooting video. Amusement park, lots of bright lights etc. but alomost no natural light (very dark evening/night).
A combination of F/4 lens and ISO1600 produced very good image quality. I also tried ISO3200 and ISO6400 but the results were not as clean so in the future I'll stick to ISO1600 and take f/1.4 and f/2.8 lenses with me.