Monero offers higher level of untraceability due to nature of CryptoNote protocol which is completely different from Bitcoin protocol. However this tech is still in very early stage of development.
Who cares ? That's pure theory and it pales into insignificance against the massive redundancy that the Darkcoin network now has with it's background pre-emptive coin supply anonymisation.
Monero is a single tier approach technology. It has to do it's "anon" in realtime at the point of the transaction.
With Darkcoin, your entire wallet has been anonymised into oblivion way before you've even decided you need to do the transaction. Darkcoin's actual mixing algo could be only half as effective as any other and yet the network will still deliver far a more secure service in terms of untraceability.
Another area where Darkcoin is architecturally optimal is in deciding what to evolve and what not to evolve. It has a 2-tier network which lets it do all its anon-development without disrupting or coupling with the commercial interface which is Bitcoin compliant. That's another area where cryptonote is sub-optimal. If Bitcoin itself hadn't consolidated so well this year I'd have said that these things were still up for grabs. But as things have turned out, Bitcoin has all but killed off all the competition. Its nearest threat was Litecoin which got to within 2% of Bitcoin's valuation at the time. It's now sitting at 0.02% of BTC's marketcap.
So what does this mean as far as commercial protocols go ? It means that any future player that wants a look in on the cryptocoin retail and trade market needs to use the Bitcoin prototcol which Darkcoin does - that was the whole basis behind its 2-tier approach.
