My amateurish take is that, for instance, a smart contract could work as an untraceable distributed Silk Road with escrow and everything else. Because there is no one machine where everything runs, it's impossible to shut down the server; there is nothing that links these transactions together, except for the commonly used Solidity code.
Bitcoin supports smart contracts, and has done so since launched in 2009. Even the simplest Alice-pays-Bob transaction is actually running a smart contract written in Script, a Forth-like language custom built for Bitcoin.
Bitcoin also supports metacoin protocols that create tradeable tokens, and has done so for a long time (e.g., ColoredCoins and MasterCoin).
Only a fraction of Bitcoin's full range of features are used today. This leads me to suspect that Ethereum's much-hyped VM will turn out to be mostly unused.
And, the majority of the interesting use cases for smart contracts require extrinsic (non-blockchain) state to operate. The price per barrel of Brent. Whether it rained over a piece of farmland. Randomness. Notice of the publication of a death certificate. All of these applications rely on a trusted server (or a federated system of them) for input. And they can be corrupted or shut down by a powerful adversary. Ethereum might be able to free itself from oracles to a small degree, but the difference will be negligible for many practical purposes.
In other words, Ethereum offers little more for day-to-day use than Bitcoin does. Ethereum does, however, enjoy a massive marketing advantage.
Interesting point, but can't randomness be read from hash of the next block? I'm not familiar with Ethereum's VM - does it not have access to that?
Miners can get into the act to twiddle the next block hash. There are some ideas on this topic here:
https://ethereum.stackexchange.com/questions/191/how-can-i-s...
Except for faster transaction confirmations, and lower fees.
A network with close to three times (28756 versus 11788) as many nodes behind it.
If you want to look at fundamentals, Ethereum is offering more for day-to-day use than Bitcoin does.
That may well turn out to be a temporary feature. Until 2015 (its sixth year of existence), Bitcoin had negligible transaction fees.
Ethereum and Bitcoin are subject to the same limitations: namely that every node requires every transaction to fully validate the chain.
Both systems are also subject to the same limitations that will throttle "mass adoption:" the need to secure cryptographic material from network-based attacks.
Ethereum is effectively a generalized distributed computer -- so new types of contracts can be written, tested, and iterated on readily, without requiring a change to Ethereum itself.
> Ethereum does, however, enjoy a massive marketing advantage.
I really don't think that's true. I'd wager that the majority of the public that is aware of Bitcoin has no idea what Ethereum is.
https://en.bitcoin.it/wiki/Script
Opcodes and values can be combined to yield a vast array of possible contracts, just like any programming language.
Templates are not used, except to activate the full language capabilities (i.e., P2SH).
Ethereum is effectively a generalized distributed computer -- so new types of contracts can be written, tested, and iterated on readily, without requiring a change to Ethereum itself.
Bitcoin is not a generalized distributed computer, but it does allow new types of contracts to be written, tested, and iterated on readily, without requiring a change to Bitcoin itself.
I really don't think that's true. I'd wager that the majority of the public that is aware of Bitcoin has no idea what Ethereum is.
Nevertheless, Ethereum - through the Ethereum Foundation and is sizable war chest, has a far more concerted marketing effort.
It's not Turing-complete and doesn't even have loops (or goto to provide an alternative). Definitely not "like any programming language", you could as well try to use Brainfuck (which is, BTW, Turing-complete).
This seems exactly the kind of applications Ethereum was meant for; however, is there a dispute resolution organ?
I'm not sure of the details, but this blog post may answer your question about dispute resolution (& malicious actors)
https://blog.district0x.io/introducing-the-district-registry...
Coding on Ethereum is hard, and this project is ambitious.
Scamming was rife, but largely mitigated by the fact that the dealer cant effect their reviews and nor can the buyer. The dealer has the choice to not sell to you based on your history, the buyer has the choice to not buy from a dealer with a bad history.
Other than that, bitcoin had little to do with its security apart from providing anonymity. If it was possible to do so anonymously you could have just post them cash.
For example: We want to prevent underage users and duplicates. We do that by manually screening IDs. Hard to do that on a decentralized system...
Another major issue: In sex work, clients present a significant threat. An abusive client needs to be reliably banned. Having them put up a deposit is just not a substitute. E-commerce do not have this as client only receives what seller sends and poses no risk to seller.
We from our central point-of-view can detect rings, ban money launderers and traffickers, investigate and appeal if needed. Decentralized system that adds such a feature is ripe for gaming.
And yes: Single point to make money, campaign, run ads, provide incentives (sign-up-friend, get-$50-credit) and organize labor...this is an important aspect as well.
On the other hand, money can be made from supervision.