At the same time, for localization a verb needs to be translated into XX languages. The default Yes/No/Cancel text is already translated. Of course that's not much of an argument since you'd have to translate the rest of your program too but is there something to be said for helping people not familiar with English to be able to use your untranslated program?
Buttons & Labels: http://developer.apple.com/library/mac/#documentation/userex...
Alert Dialogs: http://developer.apple.com/library/mac/#documentation/userex...
edit: It's also cool to see how much has (and hasn't) changed over the years. Here's a 1995 version of the Macintosh HIG: http://dropbox.scripting.com/dave/misc/appleHumanInterfaceGu...