Major - P3 Insert operations to collections system.profile and system.namespaces finished successful, but new data didn't appeared there. I think it would be good if an exception would be thrown here.
$ mongo
MongoDB shell version: 2.0.2
connecting to: test
> use newdb
switched to db newdb
> db.getCollectionNames()
[ ]
> db.tmp.insert({"field": "value"})
> db.getCollectionNames()
[ "system.indexes", "tmp" ]
> db.system.namespaces.find()
{ "name" : "newdb.tmp" }
{ "name" : "newdb.system.indexes" }
{ "name" : "newdb.tmp.$_id_" }
> db.system.namespaces.insert({"name": "newdb.newtmp"})
> db.system.namespaces.find()
{ "name" : "newdb.tmp" }
{ "name" : "newdb.system.indexes" }
{ "name" : "newdb.tmp.$_id_" }
> db.setProfilingLevel(2)
{ "was" : 0, "slowms" : 100, "ok" : 1 }
> db.system.profile.insert({"field": "value"})
> db.system.profile.find()
{ "ts" : ISODate("2012-01-06T13:30:46.592Z"), "op" : "insert", "ns" : "newdb.system.profile", "millis" : 0, "client" : "127.0.0.1", "user" : "" }