Thanks for your comments and links on this. I haven't had time to fully digest them - there's a lot of information there and there are some competing demands on my time.  From what I've seen, adding cores does not produce linear improvements, even with the small numbers of cores in a CPU. But if MC is vulnerable to GPU mining, I'd like to see it fail fast, so I'd encourage you to post any ideas you have for how one might go about creating a GPU miner.


Actually, MC has gone backwards on this a little by always sending change to first address in a wallet to support the voting system, and because this is more intuitive for new users. Generally with MC where there is a choice between ease of use and anonymity, I'll choose ease of use. I care about privacy too, but I care about adoption more. The privacy options of Bitcoin are obviously still there in the protocol, but users will need to take more care to ensure they are utilized.