Yesterday I mentioned a new review of Low Noon, which I am editor. I think reviews are important, as people can't buy your book if they don't know about it. On the other hand, I've gotten a fair number of reviews in the past few years and they really have not generated that much in sales. I think there are reviews and there are reviews. Publishers Weekly and major papers like the New York Times have a lot of clout--especially with libraries and bookstores. Unfortunately, a lot of the small web based outfits seem to have little influence. Even our review of Six Guns Straight From Hell in the Denver Post (a large newspaper) did not really generate many sales (if any at all).
Science Fiction Trails is a case in point. It's gotten some decent reviews over the past few years (and a few nasty ones in its early days) yet I can't honestly say that's brought in very many sales. Likewise, if we were to start doing reviews in our magazine, I can't say that it would really do that much for the publications we reviewed. We do run ads and there isn't much evidence those ads have generated much in sales, either.
I don't have the answer to this. I just note that getting a review is not always that big a help in the sales game. My name's David and I approved this message.