Since its inception four years ago and its rise to fame, we’ve always wondered what Twitter’s business model is. Or if it even has one.

It seems that with the sheer number of individuals and companies gaining popularity and indirectly making money through its real-time platform, the microblogging giant should naturally have at least a piece of the action. But it felt more like Twitter was taking its sweet time, prompting many to consider its possible fate of being a victim of its own success. That era of a slow and thoughtful approach to monetization, however, ends now as the company unveiled this week what it calls “Promoted Tweets.”

According to the official announcement posted by the microblog’s co-founder Biz Stone on the Twitter Blog, Promoted Tweets are ordinary tweets that businesses and organizations want to highlight to a wider group of users. These will first appear as ordinary tweets visible only to the followers of that specific brand. If the tweet is from an advertising partner, it will eventually upgrade to Promoted status and will now appear at the top of some of Twitter.com’s search results pages. It will still retain regular tweet functionality like replying, Retweeting and favoriting.

“Since all Promoted Tweets are organic Tweets, there is not a single “ad” in our Promoted Tweets platform that isn’t already an organic part of Twitter.” Stone clarifies. “This is distinct from both traditional search advertising and more recent social advertising.”

As of writing, Twitter lists international brands such as Red Bull, Sony Pictures and Starbucks, along with Best Buy and Virgin America, as the first wave of advertising partners.

Apparently, this is merely phase one of the program and is has only been rolled out to give Twitter an understanding of the resonance of Promoted Tweets, user experience response and gauge advertiser value. Stone adds that as it matures, they plan allow it to be displayed by third party Twitter clients and “expand beyond Twitter search, including displaying relevant Promoted Tweets in your timelines in a way that is useful to you.”

Twitter also believes that Promoted Tweets will be useful for its users since they will be relevant with their search queries. We tested this by searching for Red Bull and it indeed yielded Promoted Tweets but didn’t do so when we searched for tweets about the band Weezer. If it retains this unobtrusive yet useful nature, Twitter can expect continuous support from its users while seeing more and more brands signing up in the coming months.

“This announcement is a long time coming and we’re thrilled to finally be able to share it with you. As this project matures, there will be more to talk about. We will learn a lot as the program grows.” Stone, furthermore, said.

Tags: Biz Stone, Business Model, Business Strategy, Micro, Microblogs, Promoted Tweets, Social Media, Tweet, Twitter