Instapundit is reading Radical Evolution and remarks on the prospect of humans creating a superintelligence that wipes us out:

But while I think that the Singularity is something to take seriously, I also think that the focus -- shown in the interview and the passages surrounding it -- is a bit myopic. The fear is that we'll wind up creating superhuman intelligence, and that it will quickly take over the world. Personally, I suspect that superhuman intelligence will be harder to create, and less superhuman, than many suspect.

...

The bigger danger won't be the creation of a godlike artificial intelligence. It will be the creation of many millions (and eventually billions) of individuals with powers that would have been until recently regarded as godlike, in the rather small space that humanity currently inhabits.

I don't think they even have to have powers that are regarded as "godlike". I'm reminded of Philip K. Dick's short story Autofac, short for "autofactory", about a postwar world in which automated, replicating factories were used to drive the war effort. In the story, the war is over, but nobody knows how to turn off the factories, which just keep on replicating and chewing up all the natural resources to the point where there's hardly anything left to survive on anymore.

In this sense Reynold's is right...the machines don't have to be superintelligent to wreak holy havok. If the right kind of machines were given even the rudimentary intelligence of ants, and were equipped with the ability of self-reproduction, that just might do the trick.

But it's that last bit that actually ironically might be more difficult to imbue in machines. We have a hard time coming up with a laptop battery that lasts more than a few hours. Kinetic machines that are able to sustain themselves for long periods of time energy-wise, much less produce more of themselves, are a long way off.

So don't be too afraid...yet.