In the API documentation for node-mongodb-native v2.0, a few of the examples for Collection.createIndex actually show the usage of Db.createIndex.

Specifically example 1 and 4, found here: http://mongodb.github.io/node-mongodb-native/2.0/api/Collection.html#createIndex

The usage and parameters for the createIndex function example refer to:
https://github.com/mongodb/node-mongodb-native/blob/2.0/lib/db.js#L883

rather than: https://github.com/mongodb/node-mongodb-native/blob/2.0/lib/collection.js#L1267

I wouldn't mind putting in a PR to fix this myself, but I cant find where the docs for this project reside..