I was on the Oshkosh ferry flight with mostly WN employees and pilots. I overheard two pilots in the row behind me talking about the -800 seating configurations. They metioned that the new WN -800s will have a configuration consisting of 175 seats.
On a side note, I also overheard discussions that Hawaii is in the process of being added to the route map beginning in 2013.
Take these statements for what they are worth, simply conversations I overheard.