First - The action scenes and visual splendor make this a fun romp for the eyes. It's cold digital landscape is beautiful in its own way.
The thing that I was most worried about going in was the story. I knew the action and the visuals would look good but could the story keep me interested. I was very surprised with a yes. The script could use some more development.
There seemed to be a lot of back story and world building that had to be glossed over but I think overall you got enough that it remained clear enough to follow along.
The characters were well acted and interesting to watch. The most two dimensional character is probably Sam, but the good acting kept the harm of the character's script to a minimum. Quora is a nuanced delight and Jeff bridges Flynn and Clu were two sides of the same coin and absolutely brilliant to watch.
Overall I think it's worth the price of admission and I would even be curious to visit the digital world of Tron again.
Though this movie is obviously designed to appeal to the kids there is plenty for the adults too. Between the dry sharp wit of the main character to the overall story of friendship and overcoming difficulty. The action is superb and the 3D definitely adds to the excitement. You will laugh hard at some of the antics. Whether you have children or you're just young at heart this one is definitely worth seeing!