The main Ethereum Foundation’s researcher presented a short-term and long-term roadmap at Devcon opening in Prague.
After a short excursus to the history of Casper and Sharding Buterin claimed that the fourth phase of Ethereum – after Frontier, Homeatead and Metropolis – would start in the near future. He says that Serenity is implementation of all these researches, it is a completely new blockchain in terms of data structure, but it is connected with Proof of Work (PoW) chain. Proof of Stake (PoS) chain will have information about hashes of PoW chain and it will be possible to move ETH from PoW chain to PoS chain. Thus, this is a new system connected with an old one and the long term goal is to make this system work steadily, it will be possible to combine all the apps in the existing chain of blocks on one shard of a new system which will be EVM interpreter.
According to Buterin, a new model of consensus will allow to increase capacity by 1000 times and the network will be able to process 14000 transactions per second instead of 14 that it processes now. It is supposed that the test network will be launched in Q1, next year.
In other words, the tea, hopes that Proof of Stake will be implemented next year. But it will refer to decentralized apps, not to transactions.