Peskaa, I never assumed you were a studio photographer - I just figured you like to stir things up, and nothing wrong with that. However, if you have a problem with pushing the limits of technology today, that's certainly your right. But, like you, as a "card carrying" photojournalist and former full-time newpaper photographer for a smaller daily I often found myself in conditions that most big-time SI type photographer never would find themselves, unless they came with lots of extra lighting or strobes - high school gymnasiums, high school night football games, volleyball, on and on. Sure, this wasn't glamorous, but it was extremely difficult to get available light action shots that were sharp even with f/2.8 lenses and 1600 film, presuming we needed color. The big-paper guys had the pro sports arenas rigged with strobes in the rafters and radio sync devices, something I never had access to.
If Nikon and others can push the technology of sensors to make much higher ISO sensitivity useful, then why not? Why do we have to be bound by the philosophical bounds of old film thinking, whereby ISO's must end at 3200, and all equipment, including lenses must be designed exclusively with that limit in mind. It's really, in the end, a question of whether or not we can accept in our minds the rapid advancement of technological capability. My first computer had 64k RAM. My first Mac had 1MB RAM. My previous laptop had 500mhz processor and 6gig HD, and now things are almost infinitely more capable. I'm expecting the same evolution in photo sensors, not only in density and light sensitivity, but in dynamic range, and that it will have a huge impact on the way we view, and practice photography in the future. Get used to it. It's going to be a new paradigm, and we'll see photography we've never seen before because of it, and much of it done with lenses we can actually carry without breaking our backs.
At least that's my take on it... and I'm probably not even close to what will really happen down the line.
Edit: Since you are indeed acknowledging that in a few years the technology will reach a point where you will find high ISOs useful, just wait until then to buy a Nikon. In the meantime, if they don't keep pushing the boundaries with their current products, they won't get there. I'm not sure why you were so adamantly critical of the current product. You don't get there overnight, and each evolutionary phase gets us another step closer to....the next evolutionary phase. There really is no end to this concept. When is good enough... good enough? When capability increases, the demand for even better capability increases. We see it in computing. We'll see it in photography as film slips further and further into the past. And I like film... I really do.