That's some good gouge there. I guess I should have clarified, does being in-residence at NWC and taking the junior level (i.e., O-4) get you a Master's?
Finally, I also think it good to clarify that the equivalent of NWC for the Air Force is actually Air University. Air War College (a component of AWC) is only the O-5 level course. Air Command and Staff College is the O-4 level course. Therefore, even though we Navy guys typically say "Air War College" to be equal to NWC, it is really only equal to the one level of NWC.
Going through either the Junior Class (Phase 1 / College of Naval Command and Staff) or the Senior Class (Phase 2 / College of Naval Warfare) get you the exact same degree.
The Air Force has two distinct schools (ACSC and AWC) at Montgomery but they are different. The Army has Command and Staff in Leavenworth and War College in Carlisle PA.
The Navy has both schools in the same building in Newport. The syllabus are different between the two schools, but the electives are common, so while you core courses (JMO, S&P and NSA) are Junior/Senior specific, in your elective you'll have folks from the other "school" sitting in with you.
In the Navy we will call the school in Newport the Naval War College. So even those folks who are going to the College of Naval Command and Staff (Phase 1/Junior Course) will say they are going to "War College" since it's all one school. However, when you are here, there are very distinct differences between the two schools.