Yu Na Kim is already widely regarded a top 5 female skater of all time, and the best ever by some. If she successfully defends her Olympic Gold in Sochi would she be the best female skater ever. I believe she would for a variety of reasons. The only others who have multiple Olympic Golds are Henjie and Witt, and nobody considers them the best ever. It would also be impossible to say Michelle Kwan is better than Yu Na Kim with the latter having 2 Olympic Golds and Michelle 0, and when Yu Na has better records at every venue except the World Championships than Kwan (Olympics, Grand Prix final, regular grand prix, etc...). People like Ito and Janet Lynn are highly revered and rightly so but they certainly dont have the medal haul of Kim even now, let alone with her 2nd OGM.