I personally wonder what, if anything, will be the big differentiator in terms of the PS4 (or, indeed, the next-gen Xbox) when compared to the current offerings. Despite the significantly better hardware underpinning the new systems I don't expect to see massive advances in terms of visuals. I don't expect to be playing games at true 1080p with a rock-steady 60fps+ with "ultra" level effects enabled. Hopefully we will see some new and novel games, new and improved methods of interaction and so forth. I also hope that networking (whether it be Sony's offering or Microsoft's) is slick and streamlined seeing as everything is very much heading in that direction. It's good that consoles will effectively be free of the DirectX9-like level of features, too, so the more powerful GPU's (and the ability to leverage them through newer shader models and richer instruction sets) will potentially result in some new and improved algorithms for enhancing physics, rendering performance, lighting, shading, and so forth. These changes also mean that developers can take a lot of their skills they've developed and nurtured in working on multi-core/processor/thread x86-like architectures and apply them efficiently to the new platforms without having to have wildly varying code paths for each. All IMHO of course.