What memory card capacity should I use for Nikon D7000 HD video?

I'm going to buy a Nikon D7000 and going to shoot 1080p 24fps video. I wonder what memory cards I should get. What I wish to know is how much video I can shoot with let's say a 8gb and a 16gb. (32 and the others are kind of expensive but if you tell me I can only have 20 min in a 16 gb card then I'll have to buy something "bigger").

For video, the faster and bigger the card is, the better. That means you'll have to go expensive.

I shoot a Canon t1i with HD and i'm using 8gb / Class 10. Class 10 is the fastest card available right now and records my HD video easily. You can use a class 6 but it won't be as fast. If you use a class 4 the camera will stop recording in just a few seconds because the memory card can't keep up with the huge data flow.

I'd also suggest you pick up at least 3 cards if you plan on shooting a lot. They're about
$25 each