After the flight, when Commander McGinnis spoke of air mail service becoming a reality in the near future, he was not making a hyerbolic statement. Even though it was not noticed by most of the press, and not mentioned by the Navy, Commander McGinnis's P2Y-1 actaully took on mail for delivery in Hawaii. Included in the mail were several types of postcards celebrating the flight (Below).

Postcard images from eBay - eBay.com