Depends on where you are buying it. In New Zealand, the Specialized importer bought up a bunch of 2015 Turbos and sell those instead of the 2016 because the battery is a bigger capacity. The colours vary between model years.
In the US, they are identical. My LBS is currently selling a "2016" at $3,000 USD that was manufactured in October of 2014 and has MY2015 on its serial number plate. In the 2015 model year, this same bike sold for $3,800 USD.