If you look at a lot of the best practices documentation for Tor it makes everything sound like a huge hassle [1] so I can believe making a system secure against the concerted efforts of law enforcement is complicated.
[1] http://lifehacker.com/how-can-i-stay-anonymous-with-tor-1498...
This is a p2p system meaning that by definition you cannot take the market down by arresting a single person. It doesn't say it is secure against everything. It just says that as long as the source code/binary is somehow available, it will not be possible to completely shutdown.
The beauty is security vulnerabilities come and go (as in gets patched) so those are not the main concerns here. Even if they decide to tap every communication to identify the transactions and manage to decrypt it, it is going to help for a single raid and then it will get patched.
But I'm going to reserve judgement until I've seen it working.
It is human intelligence or infiltration by actors with a hidden loyalty. This has worked since the time immemorial for all sorts of security systems.
For FBI to bring it down they'll just need to repeat what they've done with Silk Road - pose as a straw buyers, get everyone they touch on record and use them to identify/arrest the users. Put out a request for a contract killing and arrest all responders. Bonus for putting a bounty on members turning in other members.
Even if this won't "shut down" the system itself, it would make it impossible to use safely.
* attacks are hard to predict
* law enforcement is interested in attacking
* being hosted on a single server is just one way to make something attackable
* the proposal needs more work
* whether this actually works is an open question
* the real question is whether law enforcement will be able to attack
In a nutshell, this is circular logic that ends where it begins, and makes no journeys elsewhere. It makes no technical criticism of DarkMarket, references no historical or similar examples, and offers no extra information from other sources (such as the source code).
So, I down-voted, and wonder why all the up-votes.