Visit the more recent post, Getting Started with VMware Cloud Foundry, MongoDB, and Node.js. Listen to the recorded Node.js Panel Discussion webinar.
Node.js is turning out to be a framework of choice for building real-time applications of all kinds, from analytics systems to chat servers to location-based tracking services. If you’re still new to Node, check out Simon Willison’s excellent introductory post. If you’re already using Node, you probably need a database, and you just might have considered using MongoDB.
The rationale is certainly there. Working with Node’s JavaScript means that MongoDB documents get their most natural representation — as JSON — right in the application layer. There’s also significant continuity between your application and the MongoDB shell, since the shell is essentially a JavaScript interpreter, so you don’t have to change languages when moving from application to database.