Twitter announced this morning plans to syndicate its promoted tweets on Flipboard, and Yahoo Japan. 

This is just the first step towards creating a larger ad network for Twitter. With just two partners, it's basically an experiment at this point.
But, this is a potentially big deal in the long run.
One of the knocks against Twitter is that its active users are growing too slowly. Last quarter, monthly active users were up 24%. 
This focus on active users frustrates Twitter, in part, because revenue is growing strongly. Revenue was up 114% last quarter.
The problem is that Twitter only recently really started monetizing its product. So, people look at revenue growth and assume that at some point it will slow to match user growth. 
If Twitter can successfully export its promoted tweets to all the places people see tweets outside of Twitter, though, it would be able to create a new revenue hose for itself. It won't matter if Twitter's active users never match Facebook because Twitter will be sticking ads elsewhere around the web. 
Twitter will be sharing revenue with partners that use promoted tweets. For now, advertisers will tell Twitter if they want their promoted tweets on Flipboard, or Yahoo Japan. In the long run, that process will be automated.
Twitter reports earnings on Thursday, so we expect to hear more about this program on the call.
Here is the announcement:
Promote content on and off Twitter - now syndicating Promoted Tweets
By Ameet Ranadive, Senior Director, Product - @ameet
We’ve been thinking a lot about how we can take the rich canvas of the Promoted Tweet and extend it beyond Twitter, to all the places where Tweets go today. That’s why we’re very pleased to announce our first partnerships to syndicate Promoted Tweets outside of Twitter: with Flipboard (@flipboard) and Yahoo! JAPAN.
What makes Twitter unique is that Tweets can flow from Twitter to other mediums seamlessly, like TV, websites, and mobile applications. In fact, in the third quarter of 2014 there were approximately 185 Billion Tweet impressions off of Twitter. For the thousands of brands already advertising on Twitter, these new partnerships open a significant opportunity to extend the reach of their message to a larger audience. Twitter syndicated ads will be seen by users within Twitter content sections on third-party properties, as well as within third-party content areas.
For example, let’s say Nissan is running a Promoted Tweet campaign on Twitter, but also trying to reach similar audience on a mobile application like Flipboard. Through this new partnership, Nissan could run a Promoted Tweet campaign on Twitter, with specific creative and targeting, and simultaneously run the campaign off Twitter, with the same targeting and creative in the Flipboard app. Best of all, because Flipboard already integrates Tweets into the app, the Promoted Tweet will have the same look and feel that is native to the Flipboard experience.
Thousands of web and mobile applications already syndicate Tweets to provide compelling content experiences, through products such as
Fabric and Twitter for Websites. Combine that with the flexibility and control of a Promoted Tweet, and we think marketers will have an almost infinite capacity to create large-scale, rich and well-targeted advertising campaigns across a variety of platforms.
This is the first of many opportunities to create such campaigns, one that provides both great content and monetization opportunities for our syndication partners, provides high ROI for marketers, and, ultimately, a great experience for users.