The Mazda2 is related to the Ford Fiesta, in which I've also spent time. My quick take, though, is this: The Fiesta has the flashier interior but, while it has more power than the Mazda2, I can't say I really noticed a massive difference in speed or power. (This could be because the Fiesta weighs more than the Mazda2.)

Overall, the Mazda2 is just more fun to drive and the ride is more comfortable. The Fiesta is available as a sedan or hatchback, while the Mazda2 can be had only as a hatchback.