the new movie is a lot like the original-great visuals not enough story but a good atempt at one so I will give them credit for that. My biggest complaint about the film was the overall length and the treatment that the character "TRON" was given-he was such a big part of the story in the original 1982 film-but in "TRON;LEGACY" he is reduced to an afterthought.
Well, "Tron" is basically a movie worth seeing, as you said, for the visual and musical aspects. Otherwise the story and characters kinda lack depth and a thorough development. A franchise based on "TRON", developing ideas and the likes, might be good, although they could become really repetitive(think about "I, Robot", "Matrix" etc)