A kitchen is about so much more than the cabinets and the appliances. When you take into account the whole of your kitchen, you will be thinking of the overall aesthetic that will be created in the room. From the frontals to the tiles to the flooring, everything is going to play a major part in the overall feel of your kitchen space.
Choose flooring carefully based on practicality and aesthetics, getting a good balance. It needs to be something that will last a long time and stand up to a lot of traffic in an area like the kitchen. You should consider a hard covering like wood or laminate for these reasons.
Wood is a good choice in that it will be strong and tough. It is much more expensive though, in which case you might want to think about the possibility of laminate. Choose something that looks like wood or tiles for a more premium appearance.