I'm not sure with OP doesn't address SilkRoad use cases on top of the ones he mentions, that are clearly a minority if we consider what is likely to happen.
Well, actually, one that he describes ‘journalists sharing secrets’ can be as big as the drug trade, if you read ‘journalist’ as ‘black hat hacker’ and ‘secrets’ as ‘exploits’. Silk Road couldn’t really do that, because of possible meddling from the central host, but without that risk…
