For static handheld shots it really does not mattr much. But if you are using VR from a moving vehicle or shooting a moving subject them it is good to be able to judge how well the VR is working. If you can't see the VR in the viewfinder then you have to look at each shot in the LCD panel. Also you can simply see beeter if the scen in the viewfinder is stable.
You are right. it is the final image that counts. But if that is really true why are we using digital? My 70's vintage film camera (it's an F2) still beats any Nikon DSLR. So there must be something more then just the final image that we care about.
As a rule I never shoot from a moving vehicle, at least when I want to get a good picture. To counteract the motion blur that would result would require a shutter speed fast enough to make shake reduction mechanisms unnecessary in the first place. I know what to expect from my sensor based SR system, so I fail to see how seeing the effect in the viewfinder changes anything. I still get sharp pictures when I expect them and know when they won't be saved by the SR system, so I'm not sure I buy into that argument.
And as far as the digital vs film argument is concerned, the whole reason to shoot digital is that with the modern post processing methods that we have today, there's no reason to expect any better quality from film; apart from dynamic range (which digital HDR more than makes up for anyway). The main advantage to digital is also the one that makes the in-lens vs camera based SR largely a matter of brand preference, it's that with memory cards as cheap and as large capacity as they are, you can shoot way more than the traditional 24 or 36 images at a time. I only have a 2 GB card and can easily fit 130 RAW images on it at a time, and it doesn't cost me a penny to empty it to my Mac and go out and shoot another 130 right away.
SLC