Here my answer is going to be a little different. The Panasonic GH-2 is arguably the best of the bunch. Beyond having manual controls while shooting video, it has a host of other features and abilities that make it the best suited mirrorless camera for video work, in my opinion. If you're the adventurous sort, you can even "hack" the GH-2 firmware to provide higher quality video (less compression) than it does out of the box. On top of all that, the GH-2 is the only still camera I know of that has an "all pixels" video mode. This special feature grabs 1920x1080 pixels without sub-sampling directly from the center of the frame (which means it's a crop of the entire sensor) and produces some of the best quality telephoto video work I've seen out of anything short of very expensive pro gear.
The Nikon 1 and Sony NEX are no slouches for video, either. The Nikon 1 has quite good color, better than many dedicated video cameras, plus it has manual video control (despite being a mostly automatic camera otherwise). The Sony NEX 5 and NEX 5n models have very good low-light capability for video work. Coupled with the 16mm f/2.8 you can stick these small cameras into very small spaces where you wouldn't ordinarily be able to do video from.
Most of the rest of the cameras I write about on this site do adequate video for most purposes, but none really stand out as do the ones I just wrote about.