Check out the product page:
Key differences in specs from 50 1.8D:
- This is an AF-S lens meaning it has a silent wave motor (SWM). Can autofocus on entry-level Nikons that don't have a focusing motor. Should focus quickly and quietly.
- M/A switch. Allows manual override of autofocus.
- Has one aspherical element, which should reduce aberration.
- As a G lens, it doesn't have an aperture ring. On some film bodies, aperture can't be controlled in A or M mode (it can be indirectly controlled in P or S mode).
- Minimum aperture f/16 vs. f/22 for the 1.8D.
- Filter size 58mm vs 52mm for 1.8D.
- The product page makes a big deal about the bokeh. I'm no bokeh hound but will be looking into this.
- The product page mentions Super Integrated Coating (SIC) to reduce flare but even the 1.8D already has that.
- MSRP: $220 vs. $135 for the 1.8D.