Khajiit, just as was the case with Oblivion. I did eventually create an Argonian character though, but I never played that file very much, I still mostly just completed more side quest type stuff and increased skills more that weren't already at 100 for the file for my Khajiit character.
I don't see why that should need to change. If anything, it would be that I don't bother to make a second character, because mainly if not exclusively, the character I am playing as will be of the Khajiit race, because the feline race is a, although ironic, substitute for there not being a canine one, especially if the player can't even turn into a Werewolf to play as for some periods of time.