There is no way for a smart contract to form an objective consensus about events that occur external to a block chain.
All voting is a power vacuum that fails due to the
Iron Law of Political Economics.
This press release is bullshit with no adoption and is merely to sell more ETH tokens to fools.
Augur and Slock.it and 99% of the apps/contracts announced for Ethereum are so flawed they can never work.
Furthermore, ArcadeCity does not use ETH for payment. Cash, credit card, debit, and Paypal are accepted.
The Ethereum integration is primarily to sell tokens to drivers, i.e. a way to do public offering (let's hope they comply with SEC regulations):
Arcade City will use Ethereum to issue ‘crypto-equity’ to drivers, allowing them to own up to 100% of the company by 2020.
It has nothing to do with using Ethereum to enable some new technology that improves upon Uber. It is about governance and creating a copycoin P&D in the Uber space.
More information:
http://cointelegraph.com/news/arcade-city-decentralized-blockchain-based-answer-to-uberaThey could use a block chain for drivers to sign a record of the price they are offering, and for riders to sign records giving reviews of the drivers, i.e. a decentralized database that verifies the signers so that reputation can't be faked.
But reputation can be Sybil attacked, unless a resource must be consumed in order to establish a reputation.
Payments from riders to drivers on the block chain would not be a consumed resource, because drivers could pay themselves from fake rider accounts. Proof-of-stake does not consume a resource and thus it
has attack vectors.
The solution is for riders to form a Web of Trust, where they trust friends and friends-of-friends and this reputation is the only reputation they trust.
But none of this needs atomic Smart Contracts. All we need is a way to sign hashes on the block chain and keep the data on a DHT. Which is I think the correct design for a 2.0 block chain.