My husband is a HUGE TRON fan. It was a foundational movie in his life the way that Raiders of the Lost Ark was mine. He has been praying to the Movie Gods since it was first announced "please don't screw it up." Well, he liked it. Didn't rave about it as much as he did Legacy. For my part, I enjoyed it but got a headache. Plus, there were plot holes big enough to drive a Recognizer through. Like, why did a fucking digital supersoldier have long hair and a beard? You can make him look like anything, and you make him look like Jesus? Plus, who was this new girl and what connection did she and her sister have to Kevin or Sam Flynn?
I think that this was probably Jared Leto's fanboy vanity project. I saw an interview with him on one of the late-night shows and he said that he was a huge TRON fan growing up. There was a script floating around that Disney passed on. He got ahold of it, had it re-written so that Ares would be the focus, and put a lot of his own money behind it.
I really wish that they would have focused more on the aftermath of Legacy. But, I guess they couldn't back enough money trucks up to Olivia Wilde's mansion to get her to come back.