Genyornis was a large flightless bird, considerably taller and heavier than the modern ostrich or emu. It had powerful legs and tiny wings, and probably most closely resembled its living relatives, ducks and geese. But instead of having webbed feet and a duckbill, Genyornis had large hoof-like claws on its toes and a big beak, with which it ate fruit and nuts, and perhaps small prey. Like modern birds, it had no teeth, but relied on gizzard stones to assist its digestion.
And pop over to Planet Rothschildi, where we are discussing all the emu's prehistoric pals.