ITPro summarizes research by Aperture Research Institute (ARI) on how customers are wary of vendor's Green IT marketing messages.

Green IT causing data centre confusion
Posted by Miya Knights at 4:01PM, Tuesday 11th March 2008
Organisations are adopting green initiatives but they're unsure how it will impact data centre efficiency and are wary of vendor hype.

The majority of organisations (70 per cent) are adopting green initiatives, but almost a third are unsure how their actions will impact data centre efficiency and are wary of vendor marketing messages, according to new research published today.
The Aperture Research Institute (ARI) study of more than 100 data centre professionals found 19 per cent of those with a green initiative admitted it did not include the data centre, while 13 per cent did not know whether it did or not.
Steve Yellen, ARI's principal, said: "Our study found that many organisations are adopting a green initiative, but some have left alarming gaps as far as the data centre is concerned."
Of those that did have a clear on the impact of green IT in the data centre, the most popular initiatives were cooling (named by 44 per cent), server virtualisation or consolidation (27 per cent) and the use of more power-efficient equipment (24 per cent). Only one respondent suggested powering off unused CPUs.

This isn't necessarily surprising research. In their research they mention.

The data center deserves to be a focal point for any green initiative: two-thirds of those surveyed reported that power consumption was rising, and 22% of those said it was rising rapidly. The chief cause is an increase in demand from the business for IT services. It is essential, then, that business departments are accountable for the energy their IT consumes. In the second paper in this series, we will investigate whether organizations are charging the cost of power back to business departments effectively.

This would be interesting to see the #'s from their 2nd research.