The Xbox 360 launched December 2005 here, so where are you that it took two years more to launch?
Both the Durango (xbox) and the Orbis (ps4) have reportedly the exact same quad core processor at the same speed.
It's GPU and Memory configurations that make the difference between the two.
The difference is the next Xbox comes with 8gb of standard ram, with reportedly 3 GB reserved specifically for the system and background stuff, and 5 for games / content. It also features 32gb EDRam the ultra fast ram that acts as a buffer between ram and CPU in order to speed the slower ram up and prevent bottlenecks.
The GPU is based on the 7000 AMD series
The PS4 comes with 4Gb of ram, but its the GDR5 type that comes on graphics cards and is significantly faster than the 8gb of memory in the Xbox (excluding the EDRam) 1Gb ram is reserved for the system, 3gb is available to games software.
It's GPU is based on te AMD 8000 series and likewise is faster than the xbox's on paper.
So on paper the ps4 should have 15% advantage over the Xbox's GPU, however the differences in memory (8gb + 32Mb Über fast edram. Versus. 4gb GDR5) will in all liklihood make the difference negligible.
So its looking like both the next Xbox and Playstation will be very close to each other and you can bet Multi-platform games will be even more indistinguishable than they are now, which is actually a good thing.
Where your purchasing decision will now come into play is in what additional services each of the consoles offer, and what exclusive first party titles appeal to you.
Hopefully with console hardware virtually identical to each other, this generation will have less of the fanboy BS, but that's probably just wishful thinking on my part.