Cupcakes. What is wrong with you people. Derpy is my favorite pony, and I have 3 boxes of chocolate-chocolate chip muffins in my kitchen, and I still say, no doubt, cupcakes are better. Its a tiny, hand-held cake. The perfect amount of icing to not make you sick, but still have that tasty stuff. And it can be any flavor. Muffins are bread, chocolate, or corn flavor. And you can fill cupcakes with peanutbutter or sweet cream or other things. In conclusion- tiny cakes rule, tiny bread with things in it does so significantly less.
You've clearly never had a triple chocolate muffin from the Fred Meyer bakery. They're like brownies in a muffin tin. Also, muffins can be filled just as easily as cupcakes. I used to go to a bakery that made cranberry orange muffins with cream cheese filling. While I do love cupcakes, they're usually covered in crappy cheap frosting, and I don't like most frosting.