for the record, the other four are: pandemics, synthetic biology, nanotechnology and nuclear war
When Stuart Armstrong says "synthetic biology", what is he talking about? Genetically engineered biological weapons? Mutants created by genetic engineering?
Even more than an answer, I'd like a link to some sort of discussion, whether it's a paper or an interview, of the details of his view.
A short article, quoting me and Luke:
http://www.wired.co.uk/news/archive/2012-05/17/the-dangers-of-an-ai-smarter-than-us
It makes the point that it's not the shambling robots that are the risks here, but the other powers of intelligence.