Sony Announces PlayStation 4: PC Hardware Inside@ 2013/02/21
8-core x86 CPU (built by AMD)
High-end PC GPU (also built by AMD), delivering almost 2 TFLOPS of performance.
Unified 8GB of GDDR5 memory for use by both the CPU and GPU with 176GB/s of memory bandwidth
Large local hard drive
Details of the CPU aren't known at this point (8-cores could imply a Piledriver derived architecture, or 8 smaller Jaguar cores - the latter being more likely), but either way this will be a big step forward over the PowerPC based general purpose cores on Cell from the previous generation. I wouldn't be too put off by the lack of Intel silicon here, it's still a lot faster than what we had before and at this level price matters more than peak performance. The Intel performance advantage would have to be much larger to dramatically impact console performance. If we're talking about Jaguar cores, then there's a bigger concern long term from a single threaded performance standpoint. Backwards compatibility with PS3 games isn't guaranteed and instead will leverage cloud gaming to stream older content to the box.
There's some sort of a dedicated background processor that handles uploads and downloads, and even handles updates in the background while the system is off. The PS4 also supports instant suspend/resume.
We don't know specifics of the GPU, but with approaching 2 TFLOPS we're looking at a level of performance somewhere between a Radeon HD 7850 and 7870. The highest end PC GPUs are already faster than this, but the PS4's GPU is a lot faster than the PS3's RSX which was derived from NVIDIA's G70 architecture (used in the GeForce 7800 GTX, for example).
Outfitting the PS4 with 8GB of RAM will be great for developers, and using high-speed GDDR5 will help ensure the GPU isn't bandwidth starved. Sony promised around 176GB/s of memory bandwidth for the PS4.
Leveraging Gaiki's cloud gaming technology, the PS4 will be able to act as a game server and stream the video output to a PS Vita, wirelessly. This sounds a lot like what NVIDIA is doing with Project Shield and your NVIDIA powered gaming PC. Sony referenced dedicated video encode/decode hardware that allows you to instantaneously record and share screenshots/video of gameplay. I suspect this same hardware is used in streaming your game to a PS Vita.
The lack of solid state storage isn't surprising. Hard drives still offer a dramatic advantage in cost per GB vs. an SSD. Now if it's user replaceable with an SSD that would be a nice compromise.
The new box heavily leverages PC hardware, which is something we're expecting from the next Xbox as well. It's interesting that this is effectively how Microsoft entered the console space back in 2001 with the original Xbox, and now both Sony and MS have returned to that philosophy with their next gen consoles in 2013. The PlayStation 4 will be available this holiday season.