Pinterest Opens Up Ad Platform to Smaller Businesses

MarketWatch: Pinterest is expanding its advertising business and its pool of customers to better compete with rivals Facebook and Twitter. The image-discovery site said that all U.S.-based small and medium-size businesses will now have access to its self-serve advertising platform. The company also is boosting the number of keywords and specific interests that advertisers can sell against to serve ads to the site’s more than 100 million users.