This simple phrase encapsulates so much more than just the notion of platforms capable of supporting multiple development languages. It comprises the notion of an operationalized polyglot platform, one that brings standardization to operations while providing flexibility for developers to choose the right tool (language) for the job (application).
To understand why this is so important (and game-changing) you have to understand traditional enterprise application platforms. They are largely single-language platforms (think .NET and Java EE) that are operationalized only in the sense that scripting languages are capable of remotely modifying platform configurations and restarting the daemon. Enterprise organizations have long standardized on a few key platforms as a means to constrain the costs associated with licensing (OSS gained traction this way) and more importantly, administrative overhead.