This article discusses how Hewlett-Packard is the latest company to offer container-based data centers. They join the likes of Sun Microsystems, Rackable Systems and IBM in doing so.
According to the article, HP's Performance Optimized Data Center, or POD will consist of 22 taller-than-average 50U racks that can support up to 3,500 compute nodes, or 12,000 large form-factor hard drives. The servers will be accessible from the front of the rack and cooled with HP modular cooling system components using chilled water HP will also offer a 20-foot container option for smaller environments.
Not all reaction to them has been rosy with Chuck Goolsbee of Digital Forest saying that they shouldn't be considered a long-term solution. Will be interesting to see how the market reacts to them.