On standard interfaces
One of the things that is usually cited in favour of Macs (and Windows)
is that the core of the GUI interface is more or less standardized,
unlike many Unix programs. For example, consider the huge disagreement
xterm, GNU Emacs, and Firefox about how simple copy and paste
works; surely the Mac or Windows way is better than that.
I don't think so.
My view is that it is easily possible to overdo an adherence to standardized interfaces, because standardized interfaces only really matter if you are only going to use a program occasionally. As an occasional user, standardized interfaces mean that you can carry experience over from program to program; you may be unfamiliar with a particular program, but you're familiar with how to do general things.
But if you use a program often enough, you are not going to forget how
to use it and you are better off with a good interface that helps you,
one that is tuned to the particular details of the job at hand. For
xterm's copy and paste interface may be non-standard but it
is excellently tuned to make it really easy (assuming you have a three
button mouse, at least).
(Serious editors are another example of this; all of them have arcane advanced interfaces that you have learn over time in order to be really productive with them. Sticking to just a standard interface would give you only a basic editor with limited or awkward features.)
(This is probably an obvious observation. I just feel like writing it down, if only for myself.)