When I wrote last week about Apple dropping their datacenter hardware in the form of the Xserve I received the predictable responses from Apple zealots, despite the fact that I wrote that Apple playing to their strengths was a good idea and that the datacenter simply wasn't an area they had been successful. Many wrote me directly to tell me that I was simply being shortsighted and that I should expect to see major Apple announcements any minute now about the products that will replace the Xserve in the datacenter, or that Apple hadn't given up on the corporate datacenter market, they were just going to come out with a series of products that would redefine the corporate datacenter market.
Many of the comments I received came across as wishful thinking, but for some reason there was a steady stream of commenters who seemed to believe that since OS X Server was such a great product, Apple would soon be releasing it as a server software product that would run on datacenter server hardware from other vendors.
Now given how Apple's OS X EULA is worded and their steadfast refusal to allow any competitive hardware vendor to ship a compatible computer, this seems really unlikely. Of course, now that the Mac uses pretty much industry standard PC hardware, there is an active community of "Hackintosh" fanatics dedicated to running the most recent versions of OS X on non-Apple hardware.
In true community support fashion there are dozens of blogs, how-to, and forum sites focused on this hobbyist project. If you find this something that you are interested in, despite it violating the license for OS X, you'll find that hackintosh.com is a good aggregation site and place to start for tips, tricks, and help on getting OS X running on non-Apple hardware.
But this isn't the same as supporting OS X Server in a production environment on the wide variety of available datacenter server hardware. Keep in mind one of the things that limits OS problems with OS X is the fact that Apple tightly controls the hardware that it will support. Apple simply doesn't have the infrastructure in place to support OS X on a wide variety of hardware platforms or the drivers for the hundreds of peripheral devices that make up today's datacenter.
This doesn't rule out a careful set of limited partnerships between Apple and server hardware vendors to build OS X server rack-mountable systems, but doing so would be a major change in the Apple business model. Not impossible, but I wouldn't hold my breath waiting for it to happen.
Apple doesn't talk about what they run in their own datacenters, but they have stated that that their datacenter environments consist of OS X, IBM/AIX, Linux and SUN/Solaris systems, so it would seem that OS X Server has a lot of company in their own environment and that Apple isn't trying to run it on non-Apple hardware at this time.