I read a clip from IDC guy Dan Harrington explaining why he thought the economic downturn crimped x86 server deployments more than Unix server deployments.  "It's easier to freeze purchases on x86 [servers], which are a commodity at this point," he said.
 
Easier to delay x86 deployment?  Sounds right.   But x86 server = commodity?  Hardly.

Clustering was supposed to commoditize x86 servers.   Then it was utility computing.  Then virtualization.  Then the cloud. Ten years ago, I bought into the Commodity Theory.  Whitebox servers would soon be king of the data center.   x86 is x86, right?   Everyone would soon be slapping Tyan and Asus motherboards into off-the-shelf ATX chassis. 

But that's not what happened.  In fact, the percentage of people using whitebox servers has actually dropped.  A lot.  IDC still predicts more whiteboxes, but their latest full-year estimates (2008) say that whiteboxes make up about 10% of servers deployed today -- down from about 14% five years ago, and something like half of what it was a decade ago.   Server admins have actually been gravitating away from them and toward "fancy" servers from HP, IBM, and Dell. 

Why?  Well, one reason is that the price tags on an entry-level HP or Dell x86 servers have dropped a lot, to the point that assembling your own servers won't save you money.   But lowered cost != commodity.

Clustering, virtualization, and cloud computing actually do better when run on servers that have a few decidedly non-whitebox-style features:

• OS and ISV certifications
• Plug-ins and APIs for mainstream management tools
• Big, knowledgeable user communities who've developed best-practices
• Around-the-globe support, and "one throat to choke" when issues arise.
• Automated deployment tools, power capping, and other things that lower operations costs (which can dwarf acquisition costs).

There does seem to be a growing interest in bare-bones servers.  Stuff like the ProLiant SL series and IBM's iDataPlex exemplify this trend.  But these aren't general-purpose servers, and they come with some of those key non-commodity features.