Back? Good. Let me tell you what you just bought (and thanks for trusting me, by the way). The main difference between this new "nifty fifty" and the almost decade-old ƒ1.8D is that it has an autofocus motor inside. This means you can use it with any current or recent Nikon SLR. The older lens lacks this motor and is instead driven by one in the camera, which cheaper bodies don't have.
The other change is that the aperture ring has gone. For younger photographers who never used a ring on the lens to change the aperture, this isn't a big deal. For oldies who find twisting a ring way easier than twiddling a dial, it's a shame.
And that's about it. The 50mm lenses have long been some of the sharpest (and cheapest) lenses available. This, coupled with the shallow depth-of-field that lets you isolate subjects from the background and the great low-light abilities of the ƒ1.8 aperture mean that everybody should have one. And if you put it on a crop-sensor, DX-format body, you get an awesome 75mm portrait lens.
So well done for ordering it. Now sit back and wait, because it's not shipping until June 16th.
Nikon 50mm ƒ1.8G [I Am Nikon blog]