Not sure how one can achieve ACID on distributed system without limiting scalability. In addition, these system are limited by the CAP theorem. Therefore it is bound to have problems, would be interesting to read the high level architecture.
How many people had the slightest clue that books would be replaced by Kindles, CDs by iPODs, tablets selling as much as laptops. The comments show that people underestimated the impact bitcoin would make.
I still believe its just the tip of the iceberg when it comes to Bitcoin.