ref What will replace silicon chips?
My guess is this.
http://fc04.deviantart.net/fs70/i/2010/020/2/c/dandelion_snowglobe_II_by_mondspeer.jpg
1) A very stable crystal scaffolding that is porous
2) Those holes are filled with large 'semi biological type' molecules that act as simple or perhaps complex logic gates
3) A combination of electricity and molecular lasers will be used to power the computation and store data
4) Simple software will become hardware which is just switched off when not needed (ie a chip that sorts)
you will probably have to wait until 2300ad before we have mastered fab techniques required to make all this happen.
Im seeing several factors.
1) uber reliability ( self healing of simple subunits)
2) uber low power requirements
3) uber compactness, 3d chips with high surface area...think of a sea urchin immersed in a liquid vortex
For the next 50 years we will probably still be using silicone or analogs,just highly polished and tweaked.
Remember when stuff first gets invented its usually ugly square and boxy. It is usually unnecessarily modular and the working parts distinct. Over time greater integration and unification occurs. Today we are seeing rounded heat sink fins and water cooling emerging. We are seeing sound cards and network cards integrated into motherboards and graphics cards integrated into CPU's. Tomorrow you will see the integration of the computer chip into cooling fins.
ref Also, what is the future of the keyboard?
The keyboard of the future will have a loads more buttons and keys. Read "one stroke solutions to common problems" This extra large keyboard will mostly be for power users and may have up to 1000 keys and use much of the universal iconography we use today.
In a sense the Chinese kind of got it right, but that future keyboard will utilize the sense of touch and colour to aid navigation rather than a mish mash of black n white flowery strokes.
Qwertyuiop is a 'general solution', a legacy that gets you by but it is a very long way from being optimal for power users or specialist applications.
When HD computer screens are 6ft by 3ft in size you will want to have a keyboard input system that matches the visual display. Today communicating with computers is much harder than it needs to be because we cannot afford the $$$ for very large screen acreage and very large keyboard acreage...this is strongly true for power users, hence multiple monitors the poor mans choice today.
A more ergonomic multicoloured version of this
http://img.xcitefun.net/users/2012/09/306260,xcitefun-chinese-keyboard-2.jpg
*note
While a great deal of computation can/and is made parallel you just can't beat the simplicity and utility of ghz
My quad core 4ghz(ish) computer does a passable impression of a 10ghz computer but a significant element of computation is and always will be serial by nature so a 'true 10ghz' computer will whoop mine in key areas of 'significance'
AMDs latest 8 core CPU was nicknamed faildozer because crippled cores dunt beat ghz in a straight line race.