We just posted a new interview with Tien Tzuo, CEO of Zuora, a company that provides billing and payment systems for subscription oriented companies. Zuora sees a new economic model forming not just for SaaS but for any commerce that can be conducted through subscriptions. According to Tzuo, one of the things holding back more entrepreneurship in subscriptions is the ability to accurately provision, invoice and collect on subscription services. Tzuo thinks he’s got the answer and if the $20 million C-round he just closed is indicative, lots of other people think so too. Check it out.