The substitution of bitcoin for fiat will substitute the virtue of savings/prudent spending for the vice of dis-saving/immediate indulgence. Bitcoin as currency will profoundly impact on the world's economy and culture, e.g. no more ruinous boom and bust credit cycles.
This point can't be stressed enough.
I am quite firmly convinced that the (failing) global financial/governmental system can't and will not be improved upon unless there are major changes in the underlying cultural narratives which support said systems. We can try to elect the "right people" as much as we want to but
providing systemic incentives encouraging prudent spending (spending means consuming resources!) has a much better chance at effecting positive change. This is one of my favorite things about Bitcoin and a point which the "let's regulate it and integrate it into the current system"-crowd seem to be overlooking.