@yannigr
so go buy AMD, their chips typically last for several generations, and they are not nearly as far behind the times as they were a few years ago.
The thing is (and as apache mentioned in his 2nd comment) that normal people do not upgrade their core system (case, mobo, cpu, and psu) ever during the life of a computer. Heck, I am a power who has built my own systems for almost 20 years and I have only ever once bought a CPU and motherboard seperately. I am not saying that you have an entirely invalid point, but you have to understand that home builders are a minority to begin with, and hardware junkies that buy a new mobo or CPU with each and every generation are even more rare, so your voice gets kinda lost among all of the $$ that is being thrown around by the masses who simply don't care.
On another side of the coin, Intel is making some HUGE changes right now with their architecture. Their goal seems to be to have the CPU become more of an SOC. They are already eating a few northbridge features with each generation, and with Haswell we saw the CPU eat the VRMs from the motherboard. Intel is already thinking about moving basic onboard audio to the CPU like they did with onboard video a few generations ago. And on top of it all, there are no real improvements in performance to be had. Haswell is faster clock per clock, but has serious thermal limits which keep the clock relatively low so that an older Sandy Bridge CPU that has been clocked to the moon can still meet or beat the current gen equipment.
And Broadwell with the 9 series chips is not going to be a desktop chip anyways! It is BGA1150, not LGA1150. Even if they make a few LGA parts to pascify the home build crowd it is going to have 0 performance increases as it is almost entirely a wattage shrink. Your next CPU upgrade is not coming until the Sky series, which may not be until late 2015 or even 2016. By then there will be enough mobo feature upgrades to justify a new mobo with the CPU anyways. Personally, I am quite happy with my Sandy Bridge. Games and most creative work is run on the GPU these days, so I feel a need to upgrade my GPU, but my CPU is simply not utilized enough to justify an upgrade on that front.
Even when I do upgrade again in a few years it will be for connectivity features, not for a boost in CPU capability.