Green Computing isn't a new concept but its one which is becoming more and more in vogue. After the environmentalism of the 1980s, green issues seemed to take somewhat of a backseat but since the new decade, they have resurfaced as a priority.
Maybe this is because of climate change, global warming , El Niño and the like.
This article discusses the greening of technology. Not everyone is getting in on the act but maybe they will be led into action after seeing IBM and Hewlett-Packard do so.
It doesn't make sense to green things up from a moral point of view but also from a fiscal one. That alone should be more than enough incentive.