Two days ago I received a news from Coindesk about the on-gong Ethereum "gas crisis" !

Quote: "In total, ethereum users spent 5,862 ether, or $2.7 million, to send transactions on Monday, an all-time high according to available network data. The culprit? A single exchange, China-based FCoin, appears to be congesting the blockchain with a controversial business model."

And then "A measure of computational effort, the price of gas (effectively what users pay to use the network) fluctuates according to demand. And that demand appears to be escalating to unprecedented levels. While December saw a popular digital cat breeding game CryptoKitties overwhelm the network, cumulative gas expenses at that time were less than half of this week's new heights."