$ cat blah.csv
name,location
"Bob","Somewhere, Out There"
"Chris","Right here"
$ mongoimport -h localhost -d testing -c testing --headerline -type csv --file blah.csv
connected to: localhost
imported 3 objects
$ mongo testing
MongoDB shell version: 1.6.5
connecting to: testing
> db.testing.find()

{ "_id" : ObjectId("4d372b87a0a15c6c1ae2f8ea"), "name" : "Bob", "location" : "Somewhere, Out There" } { "_id" : ObjectId("4d372b87a0a15c6c1ae2f8eb"), "name" : "Chris", "location" : "Right here", "field2" : " There\"" }

note garbage "field2" field/value in second record, coming somehow from value with a comma in first record