That blue-haired Goku is the real deal, it seems. This is the character as a Super Saiyan God Super Saiyan. Or SSGSS. Heh. But there's a good reason explanation for what's going on here.
Here you can see the reddish Super Saiyan God hair colour.
[Photo via Dragon Ball Wikia]
At the top of this article, you can see an official image of the blue-haired Goku from an upcoming issue of Shonen Jump. Some folks like the design, while others aren't exactly thrilled. In Japan, people have been comparing the red-haired, yellow-haired, and now blue-haired Saiyans to a traffic light.
The reason is because in Japanese, people say "ao" (青) or "blue*" for the green traffic signal.
So, forget the traffic light for a moment. What the hell is going on? Why does the Super Saiyan God Super Saiyan have blue hair? According to My Game News Flash, Dragonball creator Akira Toriyama apparently said that he thought red was a strong colour, but blue was weaker.
"Simply put, it's because [the red hair] looks so strong," said Toriyama. "The colour yellow has already been used, and blue isn't really that strong looking, so visually, red is easy to understand."
In retrospect that sounds like a backhanded complement for this blue-hair colour iteration, but if you really think about it, this makes perfect sense. The Super Saiyan God Super Saiyan is weaker than a straight-up Super Saiyan God, so thus, it has blue hair. Or something like that.
Dragon Ball Z: The Resurrection of F opens in Japan on April 18.
*The word can also refer to green.