my personal hunch is that the second Wembley show will be announced next week and go on sale on Friday. That way they will shift all of the remaining expensive seats this wekend to those that were hanging on for a second Wembley show. The second show will then get a full press launch and will create another ticket scramble next week.
Just my thoughts
I was hoping it would be nice and quiet like the 2nd Manchester show on the Vertigo tour.