I do believe it was a typo and they meant to say "fine voice". The "v" is right below the "f" on the keyboard so it would be an easy typo to make. If there is such a thing as a "vine" voice, I would like to know too because I've never heard of it in 25 years of writing.
Lol, it definitely says 'Vine Voice' below the name of my latest reviewer (4 stars) and it is an Amazon designation for the reviewer, I think, as it appears in the same typescript as 'Real Name' does under a reviewer's name. It just got me wondering what 'Vine Voice' means. Haha it's a mystery..
PS, it is a review in UK (If that makes any difference).
I've seen 'vine voice' too and it's sort of underlined in orange dots. I didn't answer Anna because I don't know either, and was waiting to see what it could be. It appears to be automated - could it be from a specific writers/review group? It looks official, so I don't think it's a typo and i've seen it on quite a few reviews...Odd!
"Looking for information on Amazon Vine? Vine is currently an invitation only program. You can increase your chances of being selected for Vine by providing helpful and honest customer reviews on Amazon.com. Learn more about writing Amazon reviews here."
Just found the above!