It seems that there are a few modules available for Node.js from multiple people to work with protocol buffers. Some are more or less actively maintained. I found https://github.com/chrisdew/protobuf which seems to be working fine. But is there a tried and true (officially certified) path?
There are no official implementations of Protobuf aside from Java, Python and C++. For node.js, you'll probably want to go with chrisdew since it's the one on npm. I personally use my own fork because I need to work with int64's.