I haven't gone to see the new Tron, but I definitely plan to.
I distinctively remember when the first one came out. Didn't really know the details about computer graphics at first, then an article came out in BYTE magazine shortly after the movie went big.
It was about how the graphics was done in the movie. The whole topic became just mesmerizing. I even learned what anti-aliasing was from that article.
I just looked up what kind of systems were used to create the original, and saw references to versions of PDP-10 running at 20-30MHz clock. Surprisingly high for its time it seems, but I guess this really was the state of the art for its time....