As social media continues to evolve, the lines between PR and advertising continue to blur to the point where social media marketing is considered a new form of free advertising on the web. Often users are seen as the free man power creating the new types of UGC driven marketing campaigns for billion dollar brands. Brands that succeeded in getting millions of free impressions on blogs and social networks pride themselves in cracking the secret code of social media.

Bloggers, as influencers, are positioned high up in this game, because they are trusted sources to spread the information down the influence chain. Brands need their readers to push the message out and convince the masses. Bloggers often rewarded with prizes of their own (Kmart), free trips (Hanes), landed cars (Ford Fiesta) or by the prestige itself of being included with other influencers.

As a blogger, more often I get PR pitches that are pushing the limits of “free advertising’. From posting about brand’s sweepstakes, to advertising a special sale – some of the attachments sent with those pitches often look like an oversized ad banner. My personal filtering process is very simple: I usually ask myself if Harpers Bazaar or Marie Claire will post this “ad” for free. In most cases, it’s a “NO”.

Often these messages are part of a larger marketing campaign, where bloggers are just another vehicle for pushing the main campaign message. Sure, some times these messages are relevant to the content of the blog, but so are contextual ads.

It looks like simply disregarding these pitches doesn’t do a good job, because they continue coming with even greater frequency. Brands who look to simply “use” social media and bloggers’ influence as a free impressions pool will need to rethink their model because if they need the influencers to continue support them, it will have to be a two way street.

As more brands start competing in the social media game, the “free” model will have to evolve into more meaningful business relationships. Brands who will figure out the model that fits them best, will win the competition.