[fjtorres]

Ads and reviews both fall into the same category: visibility generators.
Whether it be car magazines doing reviews and dishing out CAR OF THE YEAR awards to brands that "happen" to be their top ad buyers, or Kirkus pimping out their staff reviewers, both are channels that bring the product to consumer's attention.
Just as TV ads, corporate blimps, and swedish bikini teams or animated bullfrogs and geckos.
Are they *exactly* the same? No.
Do they serve a very similar function? Hail! Yeah!

I'm not ready to pass judgment on those that resort to paid reviews, either pro- or con-, especially since there are no proven-effective advertising venues for mass market books (other than Oprah Winfrey) but I've yet to see one paid review provider that doesn't give me the creeps.
(Then again, most of the traditional professional review venues give me the feeling of the stereotypical smoke-filled "Gentlemen's Club" where everybody knows everybody else and owns stock in their company.)