It is obviously a very realistic amount. Although, there has been so many ups and downs and finding it hard to break resistance, so for now, I would not want to keep my hopes too high as even the current value can just drop any time. But no one really knows as there are lots of surprises in the crypto world, so I guess we just have to see. End of 2018 is still a long time from now and I do not expect ETH to be the same by then, so $1000 can still be possible.