Online payment giant PayPal has transformed its IT mindset, and heavy use of OpenStack has been one of the biggest manifestations of the change. In fact, the open source cloud computing platform is now running “reliably, resiliently and at scale” within PayPal, powering 20 percent of PayPal servers and “a very significant amount of production traffic,” Ryan Granard, vice president of global cloud services at both PayPal and parent company eBay, told me during a recent interview.

Granted, neither the 20-percent statistic nor PayPal’s transformation into an open-source and devops-centric IT shop are particularly big news — Granard discussed both, as well as the company’s OpenShift-based platform-as-a-service efforts — in a talk at our Structure conference in June — but they are big feathers in the cap for OpenStack. The project has spurred an avalanche of startup, big vendor and venture capital activity since it launched in 2010, but has…