Justin,
Every 2 years the lithography process gets about twice as small, so you can put twice as much stuff on the same chip area as before ....
...... and run it at about 1/4 the power cost.
PerspectiveOriginal PCs had a 12/6 volt power supply of 350-500 watts total to run an original IBM PC. Lithography was at the 250-300nm level and individual bits and pieces of stuff could easily be hand soldered to the boards.
PC motherboards were the size of checkerboards ....
Flash forward to today at 20nm. 5 volt power supply is enough at 50 milliamp throughput (a cell phone charger). A motherboard can fit inside the palm of your hand.
2015 will see 10-14nm from several of the better players and 2-3 volt power supplies will drive these products. A couple of AA replaceable batteries can run your item at that lithography level.
The screen will be the biggest power user by far (and the only reason the devices will still require 5 volts, assuming the screens themselves don't get some sort of breakthrough technology as well).