There are rumours that Episode 7 will have a completely original story, though I feel that it'd defeat the purpose if it's intended to be called Episode 7. I do think it would be a shame to leave alone all the extended universe stories, but by the same token, if some of the original novels worked, who's to say that an original film won't? Whether or not they screw it up, being a Star Wars film, I don't see myself having a huge choice in whether I watch it or not.
EDIT While I wish that the prequels didn't exist, they do have their moments. Darth Maul was badass, as was the fight between him, Qui-Gon and Obi-Wan. While I can't say that the concept was original, pod racing is pretty darn cool, I reckon. Also, Star Wars: Battle Front 2 is an excellent game. It must be one of the console games I've spent the most time playing.