Once confined to marketing departments and media companies, the Mac is spilling over into a wider array of business environments, thanks to the confluence of a number of computing trends, not the least among them a rising tide of end-user affinity for the Apple experience.

Luckily for IT, many of those same trends are making it easier for tech departments to say yes to the Mac by facilitating IT's ability to provide enterprise-grade Mac management and support.

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"We're seeing more requests outside of creative services to switch to Macs from PCs," notes David Plavin, operations manager for Mac systems engineering at the U.S. IT division of Publicis Groupe, a global advertising conglomerate. There are so many requests that Plavin now supports 2,500 Macs across the U.S. -- nearly a quarter of all Publicis' U.S. PCs.

And Plavin is less of an anomaly than you might think. Buoyed by increased interest in the consumer arena, Macs are cropping up in more and more organizations, in large part because end-users are pushing for them.

According to NPD Research, Apple's share of the retail market has climbed to 14 percent as of February 2008. Gartner and IDC report that the Mac's share in the U.S. as of March 31 was 6.6 percent. Alongside that home-based shift from PC to Mac is a significant uptake for Apple among businesses, as Forrester estimates organizational Mac adoption tripled last year to 4.2 percent, mainly on the backs of enthusiasts seeking approval for Apple's silver boxes in small workgroups.

[ Discover the pros -- and cons -- of the Mac in business in our special report. And become a Mac pro through Tom Yager's Enterprise Mac blog. ]

Perhaps a better barometer of the trend is the effect increased Mac sales are having at outsourcing firms, which have traditionally been reluctant to support the platform due to a perceived lack of market in the past.

Centerbeam, a Windows management outsourcer for midsize businesses, is one such outsourcer eyeing the possibility of extending its services to cover the Mac, says Karen Hayward, Centerbeam's executive vice president. Security firm Kapersky Labs has already created a Mac version of its anti-virus software for release should Mac growth continue (and the Mac thus finds itself prey to more hackers), while Boingo Wireless, a Wi-Fi hotspot federator, is developing a Mac client to allow Mac users to tap into the Boingo network.

Couple this increasing attention to services with the falling away of another knock on the Mac, price, and you can see why even the federal government -- which has pockets of Mac users in a diverse set of agencies, including NASA, the U.S. Army, and the National Institute for Standards and Technology -- is prepping for increased use of Macs in business environments, having put together an official guide to implementing Mac security to conform to federal requirements.

After all, as Publicis' Plavin notes, Macs -- which cost the same as equivalently configured business-class PCs -- are cheaper to support because they are easier to support. And when it comes to diverting IT resources toward competitive advantage, doesn't ease of support sound compelling?

Read on: What has changed to make the Mac fit better