Twitter announces promotional "tweets"

The micro-blogging site announced it will begin working promotional posts into its search feeds and

The micro-blogging site Twitter announced on its blog today its introduction of "Promoted Tweets", beginning with brands such as Red Bull and Starbucks. These posts will appear at the top of relevant search results.

Co-founder Biz Stone said: "We strongly believe that Promoted Tweets should be useful to you. We'll attempt to measure whether the Tweets resonate with users and stop showing Promoted Tweets that don't resonate."

Stone went on to discuss the further phases of Twitter advertising, which go beyond targeted search results. He wrote: "Once this is done, we plan to allow Promoted Tweets to be shown by Twitter clients and other ecosystem partners and to expand beyond Twitter search, including displaying relevant Promoted Tweets in your timelines in a way that is useful to you."

The twitterverse has been abuzz at the news. The appearance of promoted tweets into users' timelines will prove a major shift for the micro-blogging site, moving away from the complete freedom of the user to control the sources and kind of information fed to them.