Negativity toward PayPerPost has generally come from the top-tier of blogs, the so-called A-Listers, many of whom have long struggled to gain journalistic credibility. PayPerPost, which pays people to review products on their blogs with questionable disclosure polices (many advertisers require "no in-post disclosure"), is seen as potentially damaging to a reputation that bloggers can deliver accurate information that some have worked hard to build.

Yet, despite all the criticism and the negative stigma surrounding the company, it has enjoyed very impressive growth and remains extremely popular with the long tail of bloggers. As our own Alex Iskold pointed out last week, making money in the long tail is very hard. So guaranteed cash for a post is attractive to bloggers who can't rely on traffic to sell advertising. Meanwhile, for advertisers, PayPayPost offers an opportunity to take advantage of the distributed nature of the long tail and get their brand message out to all corners of the web.

Further, sponsored posts may be harder for search engines to weed out than ordinary paid links, and so using PayPerPost might also drive search traffic to advertisers.

As long as people are still blogging in the long tail and as long as the blogosphere keeps expanding as a result, I see no reason why PayPerPost will slow, unless advertisers decide that the ROI for paid posting campaigns isn't good enough. PayPerPost is also an example of the truth of the "any press is good press" maxim and CEO Ted Murphy knows his company has likely benefited from negative press. "Our good friends Michael Arrington and Jason Calacanis have also done a stellar job of driving traffic and making sure the entire blogosphere knows our name," he quipped in a blog post about two of the service's harshest critics. "We simply couldn't afford that type of advertising if we had to buy it. I really need to find some time to write these guys a thank you card or send a fruit basket."