Shortly the protocol upgrade :

• The difficulty bomb is delayed, however block reward is reduced from 5 to 3
• zK-Snarks will not come in September, they will be part of the 2nd wave of Metropolis
• Same applies to PoS, will come with the next wave (Constantinople)
• There will most likely not be a hardfork (Some FUD going around about a new coin)

A very well put together video explaining the myths and truths about the upcoming hardfork, which is said to be released today on Monday on the Ropsten testnet

Geth 1.7 laying the foundation for Byzantium

The current incarnation of Geth contains all the Byzantium EIPs implemented and also features the fork block number 1,700,000 for the Ropsten testnet transition.
The block numbers for Rinkeby and the main Ethereum network will be finalized when Ropsten is deemed stable.
More info here: https://blog.ethereum.org/2017/09/14/geth-1-7-megara/