Many mainstay, client-installed business apps -- Microsoft Office, IBM's Lotus Notes, Intuit QuickBooks, and the open source EnterpriseDB, for example -- come in mostly compatible Mac versions. And, of course, creative apps such as Adobe Creative Suite and QuarkXPress have long been cross-platform. But many of these, especially enterprise apps, "are late on the Mac and aren't as elegant as their Windows versions," says analyst Gottheil.

Compatibility: Physical and virtual

The rise of virutalization, as well as Apple's shift toward standardized PC components, has also helped pave the way for Mac use in business.

First Parallels Desktop, then EMC's VMware Fusion, enabled Apple's Intel-based Macs to run honest-to-goodness Windows, not just in a separate boot volume (Apple offered that capability a couple years ago with its free BootCamp utility) but within the Mac OS environment. Users can now run Windows-only apps in the Mac OS, or in a separate window if they prefer, with cut-and-paste, shared directories, and shared hardware access. Armed with virtual machines such as these, Mac users can access the full array of applications available to their Windows-based brethren.

And thanks to the Mac's move to standard PC components, such as Intel processors, USB ports, Ethernet ports, and 802.11 wireless capabilities, such compatibility uses are falling by the wayside. As late as the mid-1990s, Macs included a series of proprietary connections, such as LocalTalk and ADB, and tapped SCSI drive interface technology found only on high-performance PCs. This hardware divide complicated not only IT work but also application development. Most of these hardware issues have been rectified, leaving just a few special keyboard keys to map between Windows and Mac OS when developing cross-platform apps.

Managing Macs in the enterprise

If you concede that your Mac users can run any software they need, either directly or via a VM, you may raise an old IT canard: manageability.

It may surprise you that Mac OS X Server and the separate Apple Remote Desktop software have for a decade facilitated Mac management, providing functionality akin to any Windows-oriented management tool. Developed for Apple's education market, these tools allow you to manage OS updates and app installations and upgrades. With Apple's Automator tool, you can automate much of the management workflows, essentially by creating executable scripts. You can also configure your Macs to boot into a network volume, to cope with drive failure, or to provide visiting employees or guests a nonlocal copy of the OS.

Apple Remote Desktop also allows you to control a user's PC for troubleshooting and technical support, as well as inventory the Macs. And Apple doesn't charge a per-client license for the software, just US$500 per copy installed on your administrators' Macs, supporting an unlimited number of clients. (You can also manage Windows and Linux clients using Apple Remote Desktop's VNC support.)

If you don't want an Apple-owned tool, consider FileWave's cross-platform management tools, recommends Publicis' Plavin. Or the cross-platform Client Management Suite from Symantec's Altiris unit, suggests Aquent's Lincoln.

For managing users, access control, and related security policies, Mac OS X Server's Open Directory works with Microsoft's ActiveDirectory, so you can apply ActiveDirectory permissions to and enforce policies on your Mac users and Mac-based file shares from ActiveDirectory. Or you can manage them from OpenDirectory, such as when you have a separate Mac workgroup whose initial policies you want to inherit from ActiveDirectory but then customize for that workgroup in Open Directory. Apple says it supports every one of Microsoft's ActiveDirectory services.