Comment 2 for bug 568652

Per the name ("Mac OS X" versus "Mac OS" versus "OS X", etc.): Apple consistently uses "Mac OS X". The name of the operating system is "Mac OS" and it's version 10 (X in roman numerals). [It should, in fact, be pronounced "Mac Oh-Ess Ten". Apple uses to be quite insistent on this when it was first released.]

Per the case: "OS X" is actually set in small-caps, not lowercase. Similarly, GNOME, KDE, XFCE, DAAP, IP, and other acronyms are set in small caps. There is an argument to be made that "OS X" is two short words and shouldn't be set in small-caps. I debated whether to use uppercase or small caps for quite a while. In the end, I decided to set them in small-caps for the sake of consistency.

If you would like to argue about the case of text "OS X", feel free to leave your argument here and I'll consider them -- I'm still a bit on the fence about this one.