The Cell chip in the PS3 gained considerable media attention before the console's launch in 2006, with Sony suggesting that the chip would power multiple devices around the home, providing for shared computational power between them.
Not long after the PS3 was on the market however, there were reports of game developers finding the Cell tedious to develop titles with. Cell also failed to gain the kind of momentum and integration into consumer electronics that Sony had envisioned.
Already there is speculation mounting about what exactly will power the PS4. One suggestion is that AMD will provide for both CPU and GPU in the PS4 by way of AMD Fusion architecture, which could go over well with developers. id Software's John Carmack has already given a nod of approval to AMD Fusion-style architecture for the future.
Still, Sony has not even officially recognized the PS4 as under development, though it must be by now. Microsoft has reportedly been giving partners glimpses of the next generation of Xbox, code-named Durango, which suggests it will take a product to the market before Sony again.