I do not know if you are aware of it, but Emerson and Cisco have partnered to create 'The Data Center of the Future', which is setting the new metric for green data centers. We (Cisco, too) are currently hosting launch meetings with resellers around the US to highlight best practices and some of the latest developments in the industry. You can find some information online here:

http://thedcofthefuture.com/?cid=welcome_con_hard


Our Green Computing Center will soon open in St. Luis (early this summer) and should do so with the only existing US LEEDS Silver certified center in the country. Emerson plans to showcase energy efficient capabilities. ...

... "These technologies and the overall design of the facility will help Emerson use 17.5 percent less energy per year than the traditional data center, according to Fox Architects, the lead designers in the project. In addition, Emerson anticipates receiving LEED Silver Certification from the U.S. Green Building Council. The energy-saving features include a solar array on the building’s roof that will be used as a source of power, daylighting features, and a reduced building footprint. As IT equipment is installed, Emerson will implement strategies recommended in Emerson Network Power’s Energy Logic plan to yield additional energy savings, putting into practice what Emerson advises its customers to do every day. " ...

http://www.emerson.com/en-US/news_center/news_releases/Pages/State-of-the-ArtGlobalDataCenter.aspx



This article found at Information Week discusses the new metrics for truly measuring your data center efficiency, and may also prove useful:

http://www.informationweek.com/blog/main/archives/2008/11/new_mpg_metric.html