In the near future, synthetic genomics technology should make it possible to recreate any existing virus for which the complete DNA sequence is known. At the same time, the advent of high-throughput DNA synthesis machines will cause the associated costs to drop precipitously, continuing the existing trend. In the year 2000, the price of custom oligonucleotides was about $10 per DNA base-pair; by early 2005, Blue Heron Biotechnology of Bothell, Washington was charging only $2 per base-pair (discounted to $1.60 for new customers). Over the next five years, the cost of synthetic DNA is expected to drop to about 10 cents per base-pair or even less, according to a recent report from the National Research Council and the Institute of Medicine. In December 2004, George M. Church of Harvard Medical School and Xiaolian Gio of the University of Houston announced that they had invented a new “multiplex” DNA synthesis technique that Church claims will eventually reduce the cost of DNA synthesis to 20,000 base-pairs per dollar. If his prediction is borne out, it will transform the economics of genome synthesis.
Some people have a hard time believing the vision for nanotechnology, because they think that self-replication will be impossible. The counter-argument is that life represents an "existence proof" for the possibilities of self-replication at the small-scale level.
If you are trying to engineer stuff using tiny building blocks and self-replication, inorganic nanotechnology makes it relatively easy to control the properties of what you make but relatively difficult to achieve self-replication. With synthetic biology, self-replication is less difficult, but controlling the properties of what you make becomes more difficult.
The orders-of-magnitude declines in cost for synthetic biology that Tucker and Zilinskas describe strike me as potentially disruptive. From an economic point of view (and I know nothing about the science), it would lead me to bet that synthetic biotech will overtake inorganic nanotech, even though right now the latter might appear to be ahead.