How long your battery is good
How to focus
Set white balance
Set your audio levels
Adjust your iris
Adjust your zoom speed (if you are going to use it, not everybody uses zoom.)
Shutter speed (not all cameras allow you to adjust this.)
How to navigate through the menus
How to find the histogram.
If it also takes stills, how to use that function.
Where are your Zebras? How do you set those?
The settings for your LCD screen/viewfinder. You can often adjust for the camera operator's eyes, for example my Dad is near sighted and wears glasses, well, I'm not and I have to readjust the camera for my eyes.
Also, its really good to know how to get back into manual mode quickly if you have a need for it such as a sporting event or news event that you want to cover. For example, maybe you are at the park getting a talking head interview and all of a sudden there is a UFO in the sky over head. You might want to switch to auto focus when focusing on infinity to get that UFO nicely crisp. Well, you get the idea.
Other things you might want to know are what kind of other devices can you hook up to and replay your video on. You might want to google what those jacks are and what they really do. Its very cool to know your gear. There is no shame in being very geeky.