Let me do my job quickly and direct you to this interview that Avon Editor May Chen and VP/Executive Editor Lucia Macro recently did at All About Romance. It is quite insightful. I especially loved this part:
May Chen: In my opinion, the online world still doesn’t have much impact on sales as, anecdotally, I’ve seen books get horrible online reviews but have done well. As far as I know, we still don’t include online reviews on our books, but that can certainly change if we see them start making a difference. Right now, the best endorsements for us still seem to be from NYT bestselling authors and from major traditional print reviewers.
Lucia Macro: Do the consumers recognize the source of the quote? I’m not sure that the vast majority of readers recognize all the online sites. When checking their rankings I’m often surprised at how little traffic they really get. We are all very plugged in, but many casual readers are just picking up a book at their local Walmart and barely have time to watch tv, much less wrestle the computer away from their kids. So an author quote might carry more weight with them.
I actually own an iPhone and prefer ebooks to paper but YMMV.
But as SarahT concluded:
Yes, why fix what isn’t broken?
Update: must attribute this link discovery to @jane_l from DearAuthor. I left my comment at the AAR site.