Bah you're all linking to the wrong lens.
The Noct-Nikkor 58mm f/1.2 is THE lens. Not only is it f/1.2 but it's about the sharpest f/1.2 lens that exists on an SLR body. The decisions against designing a lens are economy driven. It's not that they can't design one. They simply don't. Stupid management decisions chasing the entry level users. Nikon's has neglected it's entire pro lineup of lenses for absolute years. It's only been the past year or so where they've started revving up some of the nicer lenses. On top of that they've been ignoring their fixed focal lineup quite well.
I mean **** we only just got a 50mm which will autofocus on an entry level body, whereas simple observation of Canon habits would show that those getting into photography on the cheap will buy a cheap body, kit lens, and then a 50mm as their first upgrade.
It's not just lenses either. We only recently finally get a full frame camera. My guess is f/1.2 will make a comeback after every other camera body has high def video, and every lens has bloody VR, because god knows they sell much more of that stuff than exotic lenses.