I just saw this on the MSN homepage. World's largest cupcake - weighs 151 lbs and made it into the Guinness Book of Records. IMO, it doesn't really look like a cupcake, but more like round cakes stacked to resemble a cupcake?
It has to be a whole piece of cake. As far as I recall, Duff's attempt failed because it wasn't a single piece of cake.