... it seems that PR types and marketers are paying bloggers to write favoarble stories about client products. There's a story(not yet online) in the November issues of Smart Money called "Bloggers" by Anne Kadet highlighting this new (perhaps not, alas) and sordid trend. There's even a company called PayPerPost.com that as its name implies pays blogger for posts. Seems about as reputable as paying individuals and companies to fradulently click on search engine ads. (Yes, this is a real problem.)
If you have to pay for it, you are not doing it right. You will be found out, your client/organisation's reputation will suffer and the blogger in on the deal will be ignored by the 'real' people in the conversation.