We use Mongo for persistent storage and retrieval. We also use a nifty Mongo ODM, Mongoose (available from NPM), to model our schemas and connect to Mongo on our private VLAN.
We use Node for our full stack web framework. The native libraries provide unparalleled "isomorphic" functionality.
We rely on ExpressJS to serve our content simply, easily, and effectively, without the bloat-ware. Big thanks to StrongLoop for supporting this package.
We use Jade for constructing our modular UI. We also rely on Jade interpolation to pass reactive and static values from our Express server.
We rely on HTML5 for our media elements.
We use the CSS-only version, available through Bootstrap CDN.
We use npm because everyone else does.
We utilize SoftLayer for our hosting.