If PS4 comes out before 2015 I'll be royally 🤬 off! I just forked out $600 for this PS3, it'd better last a very long time.
No computing architecture has ever lasted more than six years without a replacement to my knowledge, either PC or console. The PS2 lasted six years, which amazes me because, other than the Emotion Engine, the PS2 was really a weak system after two years of its life. The 4 megs of VRam was really a bad design decision, and developers hated it. The Dreamcast had double that, and they loved it. But for those who schooled themselves on the Emotion Engine, such as Hideo Kojima of Konami and Kazunori-dono, it yielded amazing results. To this day, I have yet to see anything like the torrential downpour in any video game like the one in Metal Gear Solid 2. It was real time, in game.
The PS3 is so powerful that I believe it could well be viable for a full seven years against anything, which would put the release of the PS4 at 2013, but that's really pushing it. Computing technology is going to advance a LOT in the next four years, especially in the speed of motherboard and ram bandwidth, not to mention digital media formats. My new GeForce 260 graphics card has almost double the ram the PS3 itself has. While the Cell is extremely powerful, developers wanted more ram before the PS3 was even out. Eventually, 4GB of ram will be the norm. Devs and kids will want the new tech to push even more objects, provide better A.I., render even more lifelike, fully destructible scenery, have up to 32 cars in a race easily. And Microsoft, with its poorly designed 360, and Nintendo, with its puny next gen GameCube the Wii, will both have new consoles out as early as 2011. Possibly even next year. Of course the games won't be any better, but shiny new technology captivates the herd mentality of the consumer, and they will have the buzz. Still, SONY devs could equal almost anything they do if they harness the power of the PS3 like I believe they will, but a new console will have to come out by 2013. You can only take dated technology so far.