1. First paragraph

...and the mongoexport document for more information regarding mongoexport, which provides the inverse “importing” capability

should be

...and the mongoexport document for more information regarding mongoexport, which provides the inverse “exporting” capability

2. mongoimport doesn't have a --quiet option (which is a pity, it's quite useful)

joannac@Joannas-MacBook-Pro:~/scratch$ mongoimport -d test -c foo --quiet testfoo.json
ERROR: unknown option quiet
joannac@Joannas-MacBook-Pro:~/scratch$ mongoimport --version
mongoimport version 2.4.9

3. --verbose doesn't seem to have any action other than making the import slower – no difference in output on stdout or mongod logs. Maybe it would be visible if I turned my logLevel up but the docs seem to imply an increase in verbosity without it.

4. Put username/password before --ssl since ssl is so new, username/password is more common

5.

n the following example, mongoimport imports the data in the JSON formatted file contacts.json into the collection contacts on the MongoDB instance running on the localhost port number 27017. Journaling is explicitly enabled.
mongoimport --collection contacts --file contacts.json

6.

In the next example, mongoimport takes data passed to it on standard input (i.e. with a | pipe.) and imports it into the collection contacts in the sales database is the MongoDB datafiles located at /srv/mongodb/.

...in the sales database, which is backed by the MongoDB datafiles...

The sentence as is doesn't make sense