I don't get it
I've been curious about blades for a long time, but I've been running my entire server infrastructure as virtual machines for over 10 years now. Density of nodes is irrelevant to me. Density of resource is a different issue, but it seems to me that I can cram more horsepower per U into a rack with 1U servers than with blades because the blades have lower individual performance (presumably due to cooling limitations).
I like the concept, but it just doesn't seem to add up. Maybe if you're running physical loads rather than virtual it's a clear winner. Otherwise I'll be keeping an eye on the DL360 quickspecs.