Well, the decision probably wasn't that hard. They have spoken to consultants, determined 12 was the best way to go to get to the playoff, and they've done a crap ton of preliminary work prior to this meeting.
It's been a three way race for a while now. There has been a lot of Houston push-back for numerous reasons, so there's really only two candidates left.
It's possible that ESPN/Fox scared them from considering expansion, and that's why the meeting was so fast.
It's hard to say, one way or the other, what the speed of the meeting "means".