Taboola has raised another $15 million, led by Pitango VC, bringing its total to date to $40 million. The Series D financing comes just 9 months after raising its last round of $10 million. Taboola will use the new funds for continued international expansion and product development. CEO and founder Adam Singolda told me the company has 70 employees currently and plans to double in size by the end of 2013.

Taboola's roots are in providing recommendations for content providers to better promote their own video within their sites and also for third-party video to gain wider, targeted distribution. Over the past year Taboola has also leveraged its underlying EngageRank recommendations technology to quietly begin distributing article recommendations as well (I noticed these last month on WSJ.com).

In addition, Taboola runs a marketplace where content providers bid to place their content across a wide network of publishers' sites. The concept is somewhat similar to Google AdWords and AdSense, except for content, not ads.

Taboola says it is generating 1.5 billion recommendations each day, reaching 200 million unique users per month via a network that includes Bloomberg, USA Today, NY Times, Politico and others.