In effort of trying to get at least some performance back against PS4 that took commanding lead with 50% stronger GPU and more dev-friendly memory system, Xbox One team at MS unlocked 7th CPU core and added a slight overclocking, which has over the last year provided some wins against PS4 in heavy CPU-processing scenarios. Now it looks like Sony has updated its SDK [as quietly as always] and enabled their developers to also access 7th CPU core. Proof comes from the changelog of the recent update of FMOD, a popular audio gaming middleware.
While MS was very loud with promotion on their SKD updates [they needed a good word mouth this gen], Sony is usually very quiet on their releases, even substantial ones [PSP CPU overclocking abbility, numerous PSP&Vita&PS3 shrinking of OS memory footprint,etc]. On the same page you can find that FMOD got support for 7th Xbone core in January of 2015.
