It is said, that the PS4 is 10 times faster than the PS3 but also that it will take 3 or 4 years until its absolute power will be used by the games and that the first titles will not differ so much in matter of graphics from the PS3.
"The PlayStation 4 will use a processor developed by AMD in cooperation with Sony. It will combine a central processing unit (CPU) and graphics processing unit (GPU), as well as other components such as a memory controller and video decoder. The CPU consists of eight x86-64 cores running at a maximum of 2.75Ghz. The console will contain 8 GB of GDDR5 memory, 16 times the amount of RAM found in the PS3 and is expected to give the console considerable longevity. It also includes secondary custom chips that handle tasks associated with downloading, uploading, and social gameplay. These tasks can be handled seamlessly in the background during gameplay or while the system is in sleep mode. The console also contains an audio module, which can support in-game chat as well as "a very large number" of audio streams for use in-game.
The PS4's read-only optical drive is capable of reading Blu-ray discs at speeds of up to three times that of the PS3's. The console will feature a hardware on-the-fly decompression module boosting optical disc reading speed and buffer unread data when a game isn't actively accessing the optical drive, forming part of Sony's PlayGo strategy. Like the Playstation 3, the Blu-ray Disc drive should be capable of reading 16-layer 400 GB discs. Although the console will support photos and videos at 4K resolution, the system is not expected to be able to render games beyond 1080p. The console will include a 500 gigabyte hard drive for additional storage, which can be upgraded by the user.
The PlayStation 4 will feature WiFi wireless network connectivity (and wired Ethernet), Bluetooth, and two USB 3.0 ports. An auxiliary port will also be included for connection to the PlayStation Camera, a motion detection digital camera device first introduced on the PS3. A mono headset, which can be plugged into the DualShock 4, will come bundled with the system. Audio/video output options include HDMI TV and optical S/PDIF audio. The PlayStation 4 does not have an analog audio/video output.
Games on the PlayStation 4 will not be region-locked, so games purchased in one region can be played on consoles in all regions. Additionally, gamers can trade, lend, and re-sell their games, as buying a game means it is owned by them forever.
Sony has confirmed that the PlayStation 4 will not natively support PlayStation 3 games. While the company has yet to also rule-out on-console emulation of some previous generations, the company has detailed plans to explore cloud-based emulation of previous generations as a long-term solution to the challenges of backwards compatibility.
Sony is planning to launch a cloud-based streaming service through Gaikai, a company acquired by Sony in July 2012. The service will emulate and render previous generations of PlayStation games, streaming them to the PS4 and the Vita, over the internet."
PlayStation 4 - Wikipedia, the free encyclopedia
Sounds very good in my opinion.