The boy and I have done it. Together we have beaten the coolest game either of us have ever played (Guitar Hero is a very close second). After months of casual play we just beat Bowser (which, frankly, I thought was a bit easy in comparison to some of the levels that I freaking hated playing over, and over, and over to beat). Great game, amazing concept, awesome story; kudos to the Mario team. We had a blast playing it.