With processors rapidly evolving and therefore the requirements for more effective cooling solutions, a lot of you may be asking, 'Will there be a time when an air cooled heatsink will not be sufficient cooling for a processor?'. Well, as long as alternatives such as water cooling and peltier cooling remain expensive and difficult to install, air cooling will continue to be the preferable choice among most users for some time to come.
That said, as processors get faster and hotter, we will most likely see more heatsinks made out of better heat conductors, such as silver, because aluminium and maybe even copper may not be able to cope with the heat output of future processors and even chipsets.
In an ideal world, as processors evolve they should somehow generate less heat, thus allowing heatsink manufacturers to focus mainly on producing a cost effective, low noise computing solution. Thermal management is also a big issue for processor manufacturers during research and development. But, as they say in latin, 'Tempus Omnia Revelat' (time reveals all). So I guess we'll just have to sit back, wait and see.