Onscreen Asian Languages Tell It All
Strictly speaking for the Asian market share gains, apart from the iPod, iPhone and iPad enthusiasm working as a propellant, every Asian I've ever spoken to on the matter have always been astonished at how much better and natural their double-byte languages look on the Mac as compared to Windows. The onscreen difference, regardless of screen resolution, is similar to the difference of laser printers as compared to dot matrix.
Windows displays single-byte languages just fine, but Asian double-byte ones very poorly. It's like they're not even trying. They apply no text smoothing whatsoever, and unless you're using large headline style font sizes, you can't even tell the difference between serif and sans serif. It's just a jagged mess.
I use Windows extensively at work, and for certain tasks at home, but for all my Asian language tasks, I only use the Mac.