Tron: Legacy is a sequel to Tron, the first of the two seminal early 80's movies with CGI Elements; the other being the far more cheesy, fun, and memorable The Last Starfighter. I'm not going to go back and watch the original movie for the purposes of this - so you'll be spared a list of all the "nods" you're "supposed" to go see this movie for - but I will recount that I recall renting it when I was.... oh... 15 or so and found myself bored by it.
While the new movie should do a better job of holding people's attention, it still suffers from a certain amount of pacing problems in the middle/last two acts much like the first film and can be a nasty violator of the "show, don't tell" anti-cocktease philosophy I tend to endorse around here in that we just don't get enough of the elements people are likely paying to see; light-cycle battles and disk fights are short and simply not intense enough. There's one time where they hide a fight entirely to try and play off someone's reaction to the sounds of it that runs too long and ends up failing to be as effective as they'd like. Part of me wonders if they were too worried about getting "too Matrix-y" and not worried enough about bringing the kick-splode.
Otherwise definitely pretty in spots - although set almost entirely against the "dark" in that way Cheap CGI fights tend to occur at night in low budget films - and sounds good, but story wise its brutally straight forward in its implementation of the son seeking lost father plot arc. Although, there are some false trails initially set up implying "villains" that either don't exist or won't be explored until someone gets around to making a sequel, if ever.
Overall, it's a decent spend of money for the holidays if you're looking to have a bit of Sci-Fi.