Some options on the page:
http://docs.mongodb.org/master/reference/configuration-options/

are missing the default values.
Some can be assumed to be true/false options, but others are in need of a more explicit 'Default' value.
Here some I see that seem to be missing the default value:

• syslog
• saslServiceName
• noIndexBuildRetry
• oplogSize
• localThreshold
• noAutoSplit
• moveParanoia
• sslMode
  ...

Also, the values under 'setParameter' are nearly all sorted by alphabetical order, except few. We may want to order all of them.