"In a replica set configuration, all reads and writes are routed to the master by default. In this scenario, consistency is guaranteed."

One would hope that reading and writing a single node database was consistent. This is table stakes for something calling itself a persistent store. Claiming partition tolerance in the above is the same as claiming availability. The former claim has been made. Rest left as exercise for the reader.

Namasté.

- Lil' B

If a slave is partitioned from its master, it won't be able to serve requests. (Unless the request is a read query marked as "slaveOk", in which case you admit inconsistency.) I highly doubt anyone would claim otherwise.