Get a lens with Full Time Manual Focus, and something with low light capabilities. The problem with lenses that lack FTM focus is the focus ring isn't smooth, and it can affect your control while pulling focus. I did use the Tokina 11-16 a lot, and it worked well. But, I hated the fact that it wasn't FTM focus. Image Stabilization is also good to have, but it's not as important as the first two items.
50/1.4, 28/1.8, 85/1.8, and 2.8 zoom lenses are nice starts. I've gone up in ISO as high as 2500 doing video with decent results on the 60D, and I shoot around f2-f4 most of the time. So, you COULD get away with purely f2.8 lenses.