On Tue, Oct 15, 2013 at 3:31 AM, Cathal Garvey <cathalgarvey@cathalgarvey.me> wrote:
... If you can [EDIT: out resource a majority of the network] ... you can rewrite recent history in bitcoin, selectively permit transactions between other peers, cause general havoc.
the key is an attacker taking over some majority of the network. this is a much longer tangent, of which mining capacity is just a part, and i still assert that CPU and GPU mining doesn't factor into the overall risk from malicious peers.
The reward for mining was the bootstrap, but mining itself is a critical part of what makes bitcoin work.
in some few score years there will be zero coins rewarded for mining blocks - the financial incentive, for what it is currently, merely a transient part of the bootstrap. is mining important? sure. but that does not mean a CPU or GPU can contribute meaningfully to the current network. litecoin, as mentioned in another reply, is certainly relevant for these architectures however. and again, it is just as important to participate in the network, even if you do not mine! this will always be true, while financial incentives for mining are transient and volatile.