The VRII is slightly heaver, and feels it since the barrel is wider. I appreciate the fact that the VRII is half an inch shorter as it fits better in my Lowepro Fastpack 250; the VRI was pushing the length dimension of my bag's capacity. Neither will fit with the hood installed but you can leave it reversed. By virtue of being shorter and wider, the VRII has less of a "baseball bat" feel to it when installed on a smaller dSLR like the D90.
On my DX camera (Nikon D90) it's hard to say that the VRII has improved image quality. They're both extremely sharp, contrasty lenses. Other reports are that the difference on FX is noticeable - the corners are supposed to be much better on the VRII.
However, autofocus and vibration reduction are noticeably improved on the VRII. These are features that you'll appreciate even even if you're shooting on DX. Plus, the VRII paves the way for a future upgrade to FX.
Overall, there's no question that the VRII is the lens to get if you have a full frame camera, and it's probably justified on a crop sensor camera as well. The picture below shows them side by side.
