Software will be $70 so Sony will get more $$$ per game (plus extra shares when the games are sold day-1 online taking box-stores portions).
SixAxis controllers arent compatible, so expect a portion of people to pick up a 2nd controller on Day -1.
Maybe those expectations will keep the costs down.
But people will be walking out the store with $600 of stuff after tax.
I don't see people picking up Vita's on Day-1.