After updating to the 2.2.0 Node.js driver, ObjectIDs are being returned with the underlying BSON big endian byte order for the unixtime rather than the expected little endian:

oid = require('mongodb').ObjectID
console.log(oid())

// 2.2.0 driver

3720835756801c9b60a29d84

// 2.1.21 driver (and expected format)

57832378f392393d68cf8d06

See also: http://stackoverflow.com/questions/38295305/mongojs-objectid-produces-wrong-timestamp