The problem with selling images to someone big is that they get discounts. From what I've seen of Getty, if 'Jane' wants your image for her cookbook cover, she might have to pay $50. Great. But, if Hallmark, who has a bulk image agreement, wants that same image, they'll get it for $0.43.

I imagine CNN buys enough stock images that they have some sort of bulk agreement too. Ask for any sort of reasonable price, and you won't get it, since they can find a similar image for pennies.

It doesn't hurt to try to sell them the image, but don't get your hopes too high.