ethanolson: May I point out that everyone has missed the boat here. Yes, it works with FF but on an APS-C crop sensor it's coming in at 87mm equivalent... a perfect portrait lens. Also, with coma correction and a 9-bladed aperture it pretty much makes perfect sense in that scenario. Until now, Nikon hasn't had a good answer for portrait on crop sensors.
I fail to understand why you'd need to replace your FX lenses if you make the switch to full-frame. You'd just need to sell your DX lenses, no?