I just acquired it recently. I've made a post on FB about it, but I'll parrot my opinion here:
The guy's other movie, The Girl Who Leapt Through Time, is much like this one. It makes a poignant statement on society or human behavior at the expense of plausibility or internal logic. Even for a future internet, there's a lot of really unbelievable shit going on with the plot that makes it middling to sometimes just bad. The message is clear, that creating a world just as important as the real one opens up the floodgates to single entities gaining an intrinsic power that can't be emulated in the "real" world. One person or entity possessing the power to control traffic, the economy, even the fate of the world can't be done in the "real" world, but one of our own making creates that possibility. It's a cautionary tale about carelessly leaving the world in the hands of a virtual wasteland. That said, the way it's all executed is somewhat sloppy, just like this guy's last movie.
I did really enjoy it though, it's the first movie that has math so hardcore and pressing that it causes internal bleeding.