The large populations using Facebook, Twitter, Flickr, YouTube and other social media sites have left businesses scratching their heads as to how they can effectively tap this network of hundreds of millions of people.

At the time of this writing, just in the last year these sites have opened their APIs in more extensive ways, allowing developers to use their code and their content to cross-pollinate marketing experiences. For example, users can see what their friends are renting in Netflix, or users can recommend company experiences to friends.

The access to the networks is free, but it does require integration, so that when you write a blog or post a photo and a customer comments on it, the blog, the photo and the comment make their way automatically to the customer’s Facebook network of contacts and friends, with an extra push over Twitter.