It seems that everything will continue normally for at least 8 years, since 5 nm is on Intel's roadmap. It's hard to imagine anything much smaller than 5 nm being possible with technologies whose core component is photolithography...
IBM has been doing research on stacking multiple die and interconnecting them vertically by thousands of interconnects per square millimeter, with special cooling micro-channels taking care of the generated heat. With such an approach it might be possible to keep increasing the computational capability and probably also drive costs down by not replacing the manufacturing equipment as often.
Meanwhile, there is research in nanoelectronics, namely in methods to include trillions of transistors in a single chip. This paper (http://www.ee.washington.edu/faculty/hauck/publications/NanoSurvey.pdf) suggests that these trillions of devices will probably have to have a regular layout on the chip and that a large number of defective devices per chip will be the norm, so a method will be necessary to avoid using these defective devices.
Bacterius mentioned architectural and algorithmic improvements. True, a good choice of algorithm may make a program execute thousands of times faster, and the choice of the correct architecture might speed a programm up x times, but currently we have the luxury of BOTH architectural/algorithmic improvements and a nice 2x speedup every 20-24 months. If manufacturing technology had stopped evolving in 2007, we still wouldn't be able to play Crysis 1 on a cheap gaming PC!