I understand the spirit of your post and others who say the same thing, but with all due respect, it comes across a bit condescending. I doubt anyone here is unaware of the points you made, or believes that expensive gear will make a crappy shot awesome. On the flip side, though, expensive gear expands the limits of where and when you can get awesome shots. That is rather undeniable, if you've ever brushed up against the limits of your equipment. And I assume most of us have, if only occasionally.
To illustrate my point, I just upgraded from a 450D to 6D earlier this year. Already, there are several shots I took above ISO 1600 that I was happy enough with to share online -- and even perhaps to print in the future. In one instance, I captured a glorious sunset from a moving vehicle out the window at ISO 2000. There was no way for me to stop and get out my tripod at the time. With the 450D, I simply wouldn't have bothered trying for the shot. Thus, had I still been using it, you wouldn't ever have seen that shot in the 450D thread. So when you argue that "look at any camera's samples, and you'll find both good and bad shots" -- that's true, of course, but what you *aren't* seeing are shots that competent shooters either a) didn't try for, or b) got poor results with and deleted, because of their gear's limitations.
To bring the discussion back closer to the spirit of this thread, I can definitely find files in my own library where the clean shadows of the Sony sensor would have made a big difference. Now, it's possible to overcome this limitation by shooting bracketed exposures, but that requires a tripod. If a tripod isn't available or practical in a given situation, though, it's tough to argue the Nikon/Sony sensor doesn't provide an advantage that's visible in real-life images. This is especially true for landscapes and other outdoor work with dynamic range issues, of course.
I am not coming across as being condescending, just realistic. If there was one camera brand out there that was the best, why should anybody buy other cameras?