That pretty much will depend from the price of steem and sbd. I say that if the price of steem remains stable at around 5$ and with sbd at 8$ the growth will continue. When we will reach 1 million users ? Given the price granted and 35000 new accounts created every week we'll hit 1 million users by May 2018. The problem is not all the accounts become active so to get to one million active users much more time will be necessary. But as I said much of this growth will be up to the steem price.