She was a good friend and a bet of a lover, and even thow she is one of the best characters that will ever show up in the Zelda series. There is almost no odds of her showing up again as much as everybody wants her too.
Tbh I kinda hope the next wii Zelda is him trying to find her in some way. XD If we have to deal with another fairy sidekick I am going to be less than pleased. Midna was the best by far. She had a nice giggle, as opposed to an annoying "HAY" or a creepy "GET INSIDE ME AND RIDE ME TO THE NEXT ISLAND" type thing.