No, SpriteKit still uses the same coordinate system.
The difference is that the .sks script file that comes with the new project has changed. In earlier versions of Xcode, this .sks file had its own reference point (that is, where the "origin" of the scene is) (0,0), which leads to the fact that the origin is in the lower left corner.
In Xcode 8, the .sks file has a default reference point (0.5, 0.5), which is the center of the scene.
To revert to the previous behavior, just go into this .sks file and reset the anchor point to (0,0). Any old .sks files that you were lying should still work, as their anchor points were set to (0,0) before.
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