Here's another data point on topic:
http://www.zdnet.com/blog/green/for-...od-thing/15394
(As a disclaimer, I sit on the board of the Green Grid and AMD is a founding member)
Power is critical, but even chilled water (for cooling) and carbon are becoming real issues for data centers. The biggest challenge for every business is whether they can effectively do something about power in the data center...before regulation forces them to take actions that they may not have chosen.
Everybody wants better efficiency but they need to address it quickly, before they are forced into it.