Just so people are clear on this, Distortion Control is not applied to NEF files - it's JPEG only. If you use ViewNX2 (or whatever the current Nikon editing software is) then it will apply the distortion correction in post automatically. If you use Lightroom, Photoshop/ACR or DxO Optics Pro then each of those programs have their own lens profile corrections which may or may not be as good, or better, than Nikon's own. Those same profile corrections can be applied to JPEG's as well.
In other words, if you only shoot RAW and don't use Nikon software, this is an unnecessary upgrade for you.