Where I work we moved to blades several years ago, choosing Dell.

We then built our new server room, and now we are moving a good few racks of kit to a co-location facility.

This is where the kicker comes. As most hosting facilities were built some time ago their power and (more importantly cooling) they are not setup for racks of blades.

In the facility we are moving into we have ahd to pay for twice as much floor space and power as we would have done for 'normal' rack servers.

Baldes are very useful and you do save on space, but be aware of the hidden costs.

There is still no such thing as something for nothing!

Rick Byers is exactly right. There are plenty of datacentres which are short of space because of poorly laid out legacy systems, but very few *existing* datacentres can be populated with full blade enclosures because of the power and heat density. Processors are still getting faster and hotter, and cramming them ever more tightly into a datacentre which has insufficient power or cooling is not the first priority of most users any more.

Consolidation and virtualisation for better system utilisation are the direction forward, not intensification.

some reasoning behind the increasing usage of blade servers could be because, speed/power wise we've hit the ceiling and now need to start expanding sideways; no longer is 1 powerhouse chip enough, and they can't get much "faster" so some companies are turning to the solution of more is better