Above is BTC (top) and ETH (bot) vs USD. You'll notice they both follow the same ups and downs, with the exception that BTC is currently on an upward trend. What we may be experiencing with ETH right now is the correlation to BTC, and we may see it follow BTC back up later today.
So before you run and tell everyone $280 correction! The price is too hyped, the fall is nigh! look at the charts, and see if there's a trend first. Most cryptos follow each other, since BTC fell in the past two days and ETH fell in those same days, ask yourself this:
"Is this a trend, or is Ethereum falling because of something else?"