re no more overbooking... I was thinking about this:
With more open seats at the time of departure, this greatly increases the value of the free standby policy for A-listers. This means WN could get frequent fliers who are on the fence to switch from another airline because the probability of getting an empty seat is now much greater. While the % of seats filled won't go down that much, there is clearly a tremendous difference between a flight with 3 open seats and 4 on standby than there is with a flight that has 6 open seats and 4 on standby.
Not overbooking, the standby privilege, and the greater number of people who are able to use it means the late flights will have even more open seats. This is awesome for people who have mis-connected. I expect the number of people who get stuck overnight at a hub because they mis-connected and the one and only remaining flight tonight is full will drop like a rock. That increases the value of a WN ticket.
In other words, even if you never volunteer your seat, or never even hear an announcement for volunteers, the fact that you could miss your flight, or standby, and have a significantly greater chance of getting on board (say, 40% instead of 10% or whatever it is) will increase the value of a WN ticket, which means if the $59 tickets sell out sooner, more people will be willing to buy a $79 WN ticket instead of just jumping to another carrier for $79 where you can be almost assured of a full flight and almost no chance of getting home today in the event of an oversell or misconnection.