Like with PC's there are Macs with guts you can play with and there are Macs built like a turtle. Hooking-up externals is still easier with a Mac, though Winders XP offers a tremendous advance in that direction.

Paul's 3rd reason why folks don't switch to the Mac I think is the biggest: Platform-specific software wedded to Winders. I use 2 programs that are not on the Mac or would be sooo expensive to switch to the Mac that I'd rather not: ESRI's ArcMap and Leica's Imagine.

I think there's another reason that major corporations and the Gov is wedded to PC's--control. I remember in the beginning of the personal computer craze that one of the selling points for a massive 56K CP/M computer with an 8-inch floppy was that you could work off-line. You no longer had to contend with batch-processing and a dumb terminal. IT HATED it because they lost control of standardization and they had to hire a cadre of teenagers (practically) for PC upkeep--the IT professionals trained on keypunch, Hollerith cards, FORTRAN or COBOL. Real mens' computer science.

Slowly, slowly we have eased back into the dumb terminal mindset. Where I work the machine MUST be on the network to boot-up. Almost all programs are either authenticated or run from a server in another part of the United States. Everything that goes on the LAN is automagically backed-up as part of the permanent record. Local drives are only for scratch disk usage EXCEPT in my office because we deal with such large data files the IT guys simply cannot afford to copy every bleeding intermediary product so they grudgingly allow us to keep our expanding system of local drives.

The exception to this centralization and control is the Macintosh. http://www.uiowa.edu/~commstud/adclass/1984_mac_ad.html