The sheer simplicity of this interface and its ability to help manage many server features (file sharing, calendaring, e-mail and messaging, Web services, etc.) is amazing. It can be grasped by anyone with a moderate level of technical knowledge, though some troubleshooting will probably require a call to Apple's technical support or to a consultant. As an organization grows and staffers are hired or trained in more advanced server management, Leopard Server's simplified interface can be traded for the more traditional administration tools.

This combination of an easy interface and planned growth options makes Leopard Server a much more attractive option than Windows Small Business Server for small businesses and other organizations. Since it offers full multiplatform support, it provides an excellent option for all-Mac, Mac/Windows and even all-Windows shops. For this market, Windows Server's limitations for growth and the lack of truly simple setup and management make it notably less than ideal by comparison with Leopard Server.

Which is best for midsize to large infrastructures?

While Leopard Server stands to deliver a clear win for small business, larger organizations can be a different matter. In many cases, larger organizations tend to have an investment in an existing system for servers and/or clients. While migrations are perfectly possible, many organizations will likely be in a situation of integrating both platforms rather than making a complete switch. Leopard Server's innovations in terms of Active Directory integration make it a strong contender in many environments, particularly those that have even a modest number of Mac clients.

The emphasis on low-cost e-mail, messaging and calendaring make Leopard Server a particularly attractive option for organizations that are just beginning to look for multiplatform solutions. At present, there are no options for direct integration with Outlook or Exchange, which don't support the open CalDAV standard that Leopard Server uses, but some developers are already looking into developing such systems.

Also, the ease of configuration of collaborative tools and the fact that Apple has based them on open standards makes Leopard Server -- by itself or with Windows Server -- an ideal platform for any moderately sized organization looking to make staff interaction and project management easier. The new Directory application that leverages directory services for organizational, staff, departmental and even facilities information also makes Leopard Server as attractive as an administrative tool as it is a server platform.

For midsize organizations that want a solid system without the cost or confusion associated with Windows licensing, Leopard Server is an ideal candidate as well. With a listed price tag (US$999), Leopard Server costs the same as an initial investment in Windows Server Standard edition when the latter is purchased with five client-access licenses. Leopard Server also has a range of features typically found in some of the more expensive Windows Server releases. Again, Leopard Server's multiplatform support provides great flexibility and easy setup for environments with Mac and Unix/Linux clients in addition to Windows workstations.

Which is best for enterprise and data center environments?

Although effective in the enterprise arena, Apple has never quite managed to position its server products (beyond the popular Xserve RAID and Xsan storage products) as effectively as they deserve to be. There are any number of explanations for this, including that Apple didn't really ship enterprise offerings for many years and that, even though Apple is now shipping high-quality enterprise products, the company refuses to publish long-term road maps for them. Apple's own enterprise-level support and service have also proven problematic. Given the power and scalability that Apple's Xserve and Mac OS X Server offer, along with Mac OS X Server's relatively low cost, it is a shame that Apple has yet to get the right footing in the enterprise market.