It is true. They have been added to some of the new HP/Freedom Airlines (Mesa Air) 60-seat RJ's. As of now they're only flying from Phoenix (and some Vegas) to Tucson, LAX, Long Beach, Fresno, San Diego, ABQ and maybe a couple of others.
Configuration is first 2 rows of 1-2, for 6 seats.
Can't help you with the NW Avro's.