[simonh]

I did say 'useful jobs', by which I mean any purpose that itself contributes to economic activity. Some software is consumed by itself and serves no useful purpose in that sense, such as computer games or computer art. Those do contribute to GDP, so I was wrong to exclude them, but the impression I got from the poster was that software 'doesn't count' when it comes to the relationship between economic activity and energy utilization, whereas mostly it certainly does. Although the post seems to have been edited since, so the last paragraph does now acknowledge that software can improve resource utilization.