It's a cupcake frenzy today for celebs today.  First we saw Khloe Kardashian trying to sell 'em, and then we spotted Hayden Panetierre trying to buy 'em!  The Heroes star picked up a dozen or so treats from Yummy Cupcake in Burbank, Calif. this afternoon. Dressed in an interesting outfit and full make up, Hayden looked serious as she bought the dessert; is there something very solemn about cupcakes that we just don't get?