I'm quite sure that MS has set the specs in stone, but my guess is that they are not known to devs at this point and the alpha kits are always quite far away from the final hardware. Sony OTOH is a big question mark - even the rumors are pretty vague at the moment.
I really hope that all rumors out now are on the slower side than what we'll see in the final retail hardware.
I actually thought it was the other way around. BG's leaked has provided leaked specs for the PS4 while things still seem to be in a little bit of flux with the next xbox.
From what I've read, both should have their planned specs in stone at this point (pending minor changes), and developers should have been briefed on their planned specs. So while devs may not have actual hardware for either system, they should have a good idea what they are at least planning on doing.
Let's humor the idea of 16 single threaded cores in the CPU - what would the gain be from this? Wouldn't the silicon be insanely large, roughly big SoC size? Waste of silicon, yes?
This all depends on what type of CPU they go for, cache coherency, etc. I don't see either system having a 16 core CPU, and I thought this back when the earlier rumor first surfaced.
They only need to remain competitive against pirates. Even if nextgen can produce 5x better graphic [lowballing, it will be more], that stil five times better than Last of Us and Beyond. For many, that will be more than enough.
No matter what it'll be better than last gen, the Wii-U will be better than last gen. However if one system provides a good leap in performance, for a similar price and launch date, the weaker of the two may be impacted unless it provides additional value elsewhere.
Do you put stock in this theory? NDAs are a big deal, even between developers or engineers within a company. MS and Sony likely don't know much more than we do from rumors.