I dont think you can compare the 70-300 and the 55-300; the 55-300 is a 'kit' type lens made entirely of plastic (well, except for the glass

). I'm guessing it will go into a bundle and the 55-200 may well be phased out.
From my experience, the 70-300VR is, also, rather plasticky! Doesn't feel as solid as a 70-200 (for example); but that's secondary, I would think.
The image quality of the 70-300VR has been proven to be outstanding; and I've seen amazing results from that coupled with the D3x. It's an FX lens at its' best, but works great on DX too.
The new 55-300 only ads a 15mm at the wide-end, and would be just as plasticky as the 70-300VR. Anything worse, and it would be made of weetabix
If Nikon wanted the 55-300 to be a bundle-kit lens, why not just use the 70-300. The sales volume would help drive down the prices a bit to make it more viable too.
Also, if the 55-300 is going to phase out the 55-200VR (which was another outstanding lens by Nikon), that would mean it has to compete on price with the one being phased out; this adds another problem for the 70-300.
If Nikon prices the 55-300 close to the "to-be-phased-out" 55-200, where will that leave the 70-300VR, which is about double the price?
28-300 is to combat the indy lens manufacturers offerings, Sigma and Tamron do similar versions. People do buy them......I should know, I did....and sold it very quickly (Tamron 18-270).
Neil
A few problems here; someone buying an FX body from Nikon would, in most likely, want superior glass than what can be offered in such big range zooms.
For DX bodies, cropping this lens means its' not wide enough on the wide-end, hence the kit 18-55VR comes best; and it's conflicting with the 55-300 just announced for the long-end.
I'm curious, why did you sell your 18-270
