I assume that mining will tend to be modestly profitable. As Bitcoin scales up and as the reward goes down, either it will have to increase transaction fees and use an enormous amount of energy, or the mining reward will be too low compared to Bitcoin's value, there won't be enough miners, and 51% attacks will start to be profitable.
This isn't a problem for PPcoin, which gradually transitions to proof-of-stake instead of proof-of-work. It seems to me like it'd be more viable as a major currency.
I assume that mining will tend to be modestly profitable. As Bitcoin scales up and as the reward goes down, either it will have to increase transaction fees and use an enormous amount of energy, or the mining reward will be too low compared to Bitcoin's value, there won't be enough miners, and 51% attacks will start to be profitable.
This isn't a problem for PPcoin, which gradually transitions to proof-of-stake instead of proof-of-work. It seems to me like it'd be more viable as a major currency.