I doubt that they will die any time soon, but rather just become less customizable and overclockable. Intel is already moving in that direction with BGA boards, and NVidia restricting OCing on their cards.
I bought a Rosewill Stallion 500w with my first ever build, couldn't even handle 350 watt loads after a few months T_T
I have a corsair TX650M now though, so all is good! I love how the fan stays off under low loads.