The reference page for the replSetGetStatus command says the following about the meaning of the members.state field in the output document:

The value of state is an array of documents, each containing an integer between 0 and 10 that represents the replica state of the corresponding member.

However, in the output I'm seeing from this command, the members.state field is a single value, not an array of documents:

MongoDB shell version: 2.4.3
connecting to: localhost:27000/test
backup_test:PRIMARY> rs.status();
{
	"set" : "backup_test",
	"date" : ISODate("2013-11-08T20:00:37Z"),
	"myState" : 1,
	"members" : [
		{
			"_id" : 0,
			"name" : "localhost:27000",
			"health" : 1,
			"state" : 1,
			"stateStr" : "PRIMARY",
...etc...

Interestingly, the documentation for this field is correct in the v2.2 manual.