If the rumors are true and Sony is working on Navi tech then we could very well see Sony getting some legitimate powerful hardware at the $499 price point with a GPU packing a decent punch for a very good price in exchange for their help with R&D or whatever their roll was working with AMD.Well, they did that this gen and the games did the talking. 720 vs 1080 on so many third party titles it was a wash. There were a few outliers, but the 50% difference really did the math for them. PS4 was in all facets the better hardware for the money.
I don't think they'll go that route this time, besides with the streaming box. The hardware will be very close this time around, with the main differences possibly in Navi aspects and RAM between the two (I think one of them will opt for HBM). Xbox will likely come with a $499 price point again. I'm betting Sony ups their game to $499 as well to keep specs in line with the competition.
As far as differences, we know Sony has been working with AMD on Navi specific architecture, how far it goes is yet to be seen.
How funny it would be if they both 180, and Sony gives us the more expensive less powerful hardware and Xbox drops next gen launch price to $399. I mean, it won't happen, but what a hoot if it did. Fun times ahead.
That would be something else is the roles were reversed it's exciting times to see what they both do in these next 12-18 months.