An excellent Xbox One hardware and software analysis by Anand Lal Shimpi:
We’re still talking about over 5x the peak theoretical shader performance of the Xbox 360, likely even more given increases in efficiency thanks to AMD’s scalar GCN architecture (MS quotes up to 8x better GPU performance) - but there’s no escaping the fact that Microsoft has given the Xbox One less GPU hardware than Sony gave the PlayStation 4. Note that unlike the Xbox 360 vs. PS3 era, Sony’s hardware advantage here won’t need any clever developer work to extract - the architectures are near identical, Sony just has more resources available to use.
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Sony gave the PS4 50% more raw shader performance, plain and simple (768 SPs @ 800MHz vs. 1152 SPs & 800MHz). Unlike last generation, you don’t need to be some sort of Jedi to extract the PS4’s potential here. The Xbox One and PS4 architectures are quite similar, Sony just has more hardware under the hood.
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Sony’s approach (especially when combined with a beefier GPU) is exactly what you’d build if you wanted to give game developers the fastest hardware. Microsoft’s approach on the other hand looks a little more broad. The Xbox One still gives game developers a significant performance boost over the previous generation, but also attempts to widen the audience for the console. It’s a risky strategy for sure, especially given the similarities in the underlying architectures between the Xbox One and PS4. If the market for high-end game consoles has already hit its peak, then Microsoft’s approach is likely the right one from a business standpoint. If the market for dedicated high-end game consoles hasn’t peaked however, Microsoft will have to rely even more on the Kinect experience, TV integration and its exclusive franchises to compete.
The market for dedicated high-end game consoles hasn’t peaked because people who bought a nice HDTV want a premium game experience to go along with it, and they can’t get that from PC or mobile games, plain and simple.
It sounds like PS4 has Xbox One soundly beat on the graphical power front, but the PS3 also had greater graphical power than the Xbox 360, and yet most multi-platform games didn’t look much better on PS3 than on Xbox 360. In that case, the PS3 had an architecture whose potential was difficult to maximize. Since the PS4 and Xbox One architectures are so similar, it might be a different story.