The word on the street is that Twitter has finally developed a business model. How do they plan to make money in less than 140 characters?
Sponsored Tweets. 
According to several sources including Mashable, AdAge and the New York Times, corporations will have the option to sponsor a Tweet in searches. Unlike a normal keyword-based Google Ad, these Sponsored Tweets will still fit the same 140 character format as any other tweet. 
What's so cool about this? All free things eventually come to an end and Twitter's indulgence in ad revenue was as inevitable as Steve Jobs selling a lot of iPads. We knew the ads would come in some form or another. What makes these a different opportunity than other online ads?
Twitter ads and your typical online ad (say a Google ad) will both have some brief text and most likely a link to some home website. However, unlike a Google AdWord ad, Twitter sponsored tweets give Twitter users the ability to reply to the ads like any other tweet.
Think about it: consumers will be able to have two-way communication with paid advertising. Imagine hearing a TV or radio advertisement and being able to give direct immediate feedback directly to that advertiser. To me, this will open up a whole new style of marketing communication. Social media introduced us to the idea of brand transparency the last couple of years. Now with Twitter's new advertising platform, this takes paid two-way communication up another notch.
How do you all see this influencing the future of mass media and relationship marketing?