The ProgrammableWeb directory marches toward quintuple digits. Having just passed 9,000 APIs, the next milestone ahead looks even bigger. Of course, all the recent milestones look huge compared to the directory at the end of 2005, when it sat at just 105 APIs. In addition to continuing the rise of the enterprise, the latest APIs show mobile as a driving force. At least two previously locked-down categories, payments and messaging, are now being changed by APIs.