Perhaps....and maybe long after we are dead. So long as the U.S. has far and away the most powerful military, it's unlikely that the US$ will be replaced. I'm not claiming I like this, rather I believe this to be the reality on the ground and I'm simply acknowledging it. I think competing global currencies is healthy for a global community. .
^ you never know, something else could happen like the US breaks up because of civil wars within itself. Countries will immediately look for another currency to trade in. That be the Yuan. 2020 is when it could happen by.
It's not going to be THE official currency, it's just being added to a basket of currencies including US dollar, Pound and South African Rand. http://m.smh.com.au/world/zimbabwe-looks-to-chinese-yuan-as-legal-tender-20151222-gltspp.html