It is the "new thing", the new bitcoin? Not exactly. Ethereum is a platform based on blockchain, but while the bitcoin blockchain is used to track ownership of precisely the digital currency called bitcoin, the Ethereum blockchain focuses on running the programming code of any decentralized application. While all blockchains have the ability to process code, most are severely limited. Ethereum improves this. Instead of giving a set of limited operations, Ethereum allows developers to create whatever operations they want. This means developers can build thousands of different applications that go way beyond anything we have seen before (smart contracts):
Ether is a form of payment made by the clients of the platform to the machines executing the desired transactions. Ether can be trade independently.