I saw the preview for Tron Legacy. It looks neat, and gave me the slightest shiver of anticipation, but I've learned to squelch my hopes in these matters. In any case, it made me want to watch the original again, so I did.
I saw Tron in the theater when it was released, and I am still reeling a bit from realizing that that was 28 years ago. This movie is still fun to watch, and very pretty. Obviously, the animation will seem outdated at first, but once you give it a minute, you'll stop comparing and get into it. The computer animation, along with rotoscoping and other lighting and coloring techniques, all of which were cutting edge at the time, make for a movie that is still visually brilliant and absorbing. Ebert gave this movie four stars when it came out, mainly for the visual effects.
Tron is criticized for being light on plot and character development, and it is. But there's enough story and suspense to string together this eye candy necklace, and it's fun to see the young Jeff Bridges and Bruce Boxleitner in action. Also, there are ideas about deity incarnation and avatars in there - pretty cool!
Furthermore, now that it's 28 years old, the movie is also interesting as an artifact of the [then] young computer and video game culture.
Interesting lil' side note: According to Wiki, the Motion Picture Academy refused to nominate Tron for special effects because the creators "cheated" by using computers.