Dual-booting between operating systems is no more practical a solution for professional Mac users than it is for anyone else. In most cases, users will want to run OS X and another OS side by side. That's a job for virtualization, and because OS X will allow itself to operate as a guest OS, it has to host other x86 OSes.

This it does, exceedingly well, with help from Parallels Desktop. This solution is imperfect -- display updates could be faster and there's no support for 64-bit guests -- but it's fast, effortless, and compatible with every imaginable 32-bit guest OS. Imposing small overhead, Parallels Desktop is an entirely practical means of running alternate operating systems on a Mac.

"Apple's product line is tiny. All other Intel OEMs focus on choice."

Apple's catalog has just eight systems: iMac, 15-inch MacBook Pro, 17-inch MacBook Pro, white MacBook, black MacBook, Mac Pro, Xserve, and Mac mini. Apple departs from its Intel OEM brethren that feel it's necessary to save a place in their product lines for every subvariety of Intel CPU. With Apple, you pretty much choose the shape you like best, and that determines what Apple puts inside.

Almost. When it cut the number of base configurations, Apple also raised the number of configure-to-order options. You can't order a Mac Pro with a Celeron D, Pentium 4 Extreme Edition, or a single Core 2 Duo processor, but you can dial in up to four hard drives, two optical drives, and one of several graphics cards. Nonetheless, if you long for options in low-level items such as CPUs and chip sets, look elsewhere.