It's a little bit scary, but widget and sharing service ClearSpring said this morning that the company's media widgets and newly acquired AddThis plug-in are now seen by more than 500 million unique viewers each month, according to Comscore. That's half the people on the internet, the company says.

This morning the company announced a new API that allows developers to share any embeddable content, including YouTube videos, through the AddThis/ClearSpring infrastructure and analytics service. The company says its reach has grown from 200 million combined monthly uniques in September when it acquired AddThis to 500 million today, a huge jump in 6 months. The new API could accelerate that growth even more.