(03 November 2012) Version 1.2.2: Added support for db_name, allowing people using admin authentication to specify a db name to use, since they must connect to the admin db.
(28 July 2012) Version 1.2: Removed map/reduce to avoid certain bugs, which also simplified some of the calculations.
(03 June 2012) Thanks to @wfreeman, we now handle MaxDepth, and other goodies.
(25 May 2012) Thanks to @wfreeman, we now recognize the Date, ObjectID and BinData types.
(28 July 2012) Version 1.2: Removed map/reduce to avoid certain bugs, which also simplified some of the calculations.