Pinterest is a Pin-board that lets you share pictures and you can categorize them based on interests as you can make up boards and describe each picture. Members of pinterest can follow you like any other social network based on your interest.
If you are a internet marketer and your site or the site your promoting has allot of graphics on it for example lets say charts then clearly you can see the reasons why you can use Pinterest to your advantage in generating targeted traffic from users that like your same interests and click through to find out more info.
Make your Pins descriptive, engage your readers and hopefully they will click through to find out more. I just started using Pinterest, even though you may not have many followers you can still generate traffic from other users with your same interest.