I have a decidedly enterprise view - one that, although lives with a plurality of Windows boxes, is not by choice, but by vendor (Microsoft) design. I've run IT shops with as many as 262,000 desktop computers - about 10% of them Mac OS X machines. Tracking the total cost of ownership, which includes acquisition cost, support manhours, help desk, application installation, operating systems upgrades, and back end integration into servers, databases, security, etc. Macs cost me 1/10th to 1/25th the operational cost of a PC. Caveat: The more the infrastructure (servers and back office applications) are proprietary, non-standards compliant Microsoft products, the more if costs to get the OS X machines integrated into the environment. This cost insight is the significant irony - the argument that the proprietary Macs are more costly does not hold up under scrutiny. Ignoring that a similarly equipped Dell is more expensive than the Mac equivalent in all categories, acquisition cost of computing hardware is inconsequential in the overall cost of a computer in an enterprise. This acquisition cost is so insignificant compared to the costs of the proprietary nature of Microsoft generated data and applications. This Microsoft data (e.g Office file formats), protocol (e.g. Exchange's bastardized IMAP protocol for calendaring), and applications interdependencies (e.g. Application servers, email servers, collaboration servers, active directory dependencies) lock, places significant financial barriers to entry for any other player. In addition, the Mac’s minimum hardware diversity is a key factor in platform stability (less drivers to support). Companies that have adopted proprietary, and therefore, restrictive, Microsoft based platforms, applications, protocols, and data format, have pigionholed their companies into a situation with no clear financial migration strategy. Pinning one's hopes to a single vendor is an exercise fraught in peril, placing you at the whim of the vendor. The real key is using data formats that are application portable, application functions that have multiple alternative vendor solutions, and an environment that does not lock you into the agenda of a single vendor, all the while, creating a low cost of ownership, and minimal barriers to user acceptance. OS X provides this, as almost every effort is made in OS X to support interoperability between applications and transparent data transfer/translation. The only things that ever seem to create problems, is attempting to integrate with the proprietary (and prevalent) world of Windows back end infrastructure. Yes, fewer applications exist on OS X, but virtually every functional capability of alternative platforms, including Windows, exists. Due to consistency in human interface guidelines, and a rapid user community that demands high quality, Mac applications are easier to train users on, and Mac users regularly run a broader range of applications and functionality - resulting in the computer as a tool that garners more productivity across a greater number of user skills. I have yet to find a PC user, that, when forced to use a Mac exclusively for 30 days, has ever wanted to return to a PC - the exception being a dependency on some proprietary data that cannot be manipulated in a OS X application.
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