It's been twenty years in the "real" world, which is a heck of a lot longer in "grid" time. (In the first film, Flynn could have been in there for days, and going by the shot of Dillinger's office, the sun was just coming up when he got out.) Things change and evolve. I fully expected it would look different, and some simulations would improve. The subdued colors could also reflect the state of things under Clu's rule. Flynn obviously would have digitized things like the books to take back with him into the system. (A nice nod to the ending of George Pal's version of "The Time Machine"?)
I'd like to know how Flynn got the digitizing laser into the basement of the arcade. (Did Encom abandon research on it?) It seemed to take an entire lab building full of equipment to run it in the first film. In Legacy, it seems to be hooked up to smaller version of Dillinger's computer desk. What happened to Yori, Dumont, and all the programs left behind on the "old" Encom system? And Flynn's computer must have one heck of a stable power supply to run undisturbed for two decades in a basement!
I would have liked more of Tron. If they're saving him up for a third film, the filmmakers must be awfully confident the studio will greenlight it. I think his true programming was fighting to resurface once he realized he was fighting a user in the arena, finally seeing Flynn snapped him back. I don't think anyone is "dead" for certain. Flynn's kid got out with his father's identity disk, and he may have copied everything else off the computer into the memory card he put around his neck.
The biggest plot nit for me was how was Clu going to materialize that troop carrier into the real world? The laser is sitting in a basement!
Dillinger's son on the Encom board must be the mother of all red herrings, unless he also figures in a third film. For that matter, if Ed Dillinger isn't dead, he probably didn't do too much jail time and could even be running a rival company.
I've been a Daft Punk fan ever since I saw the "Interstella 5555" anime. I enjoyed the soundtrack, although I imagine they were told not to emulate Wendy Carlos for whatever reason.
And I agree with Edwin, major 2001 vibe on Flynn's apartment hideout. Even the "old" lightcycle evokes Bowman's space pod parked in the corner.
Am I the only one who got really nostalgic seeing a honest to goodness video game arcade? Disney should turn some of their mall stores into "Flynn's".