I have seen these little guys for all different holidays. I can vouch for the goodness of white chocolate coated popcoarn. My friend made this awhile ago for a baby shower, she used a light pink chocolate, and added nuts as well. For my VDay gift, I added M&Ms.
One ball takes an individual size bag of light popcorn, popped. I melted about 1/4 c. of white chocolate. And stirred in about 1/8 c. M&Ms.
Once the popcorn was coated, I rolled it into a ball, and then used syran wrap to hold it in a ball shape until it hardened.
I used some additional white chocolate and M&M's to dot the outside of the ball before bagging it up.