Wouldn't be surprised if they undercut Xbox, but given some of the survey results I've seen knocking about Sony may think they don't need to.
I can't see them going $600 though, they learnt with PS3 that people get sticker shock and from Xbox one too which had a higher price because of the kinect thing being included. I wonder if they will offer a $x per month plan like Xbox - I think thats a good move..
Sony never really made their money back in console sales alone. They tried in 2006 with ps3 prices. They sell their consoles at a loss and make it back in software and services. They can launch ps5 at 299$ and still make money. They aint losing any money with ps now and ps plus its mostly all gain.