The sub-header reads; "Not everyone needs a Mac Pro; sometimes a mini might do."
With the coming of Vista and it's increased costs both for licensing, software, hardware and retraining, some of the businesses I have dealings with are indeed looking toward Macs. Make no mistake about it; they WILL move away from Windows. The question is to what.
The learning curve for Linux is perceived to be too steep. The perception is more drastic than the reality, here, but there is no doubt that it will take a while to get used to the new regime.
Macs have MS Office if events prove you must have that. The OS is tied to the hardware, which is seen as an advantage for business because there is only one basic flavor of it, not the dozens of Linux distributions or the 3-4 versions of Vista that need choosing between. Macs are seen as "intuitive" and so with less of a learning curve. (I don't find that true and in fact dumped the Mac OS X when the learning curve proved too steep. I went to Linux on the Mac.) Java on the Mac is good enough that one can run one's Java software with little or no modification.
In the end; the cost of switching to Macs looks not much worse than the cost of switching to Vista. Upgrades are more manageable, as well. There is not much reason not to.