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Seriously, I think most mac-projects try to ape rather superfluously just graphics of Macintosh screen. True difference lies deeper, how interface is designed to supply simple and sensible tools. Just that there is a dock does not make linux maclike (I do not even use dock in my mac, never have used).
I have not yet seen a linux distro where menu bar is at the top of the screen (where it of course should be fo mac user!). Menu layouts are often wasteful (yes, they grew more wasteful in MacOS too when they moved from OS9 to OSX).
I grant that typefaces used in Mac4Lin interface look much better than in typical Linux distro, they are usually horrible.
In a way, Graphics is all that can be mimicked in Linux. Both Mac OS X and GNU/Linux contain a UNIX-System like core within (Mac OS X is certified UNIX but Linux is not). Other than that the one thing that separates Mac OS X from Linux is the application layer (the Cocoa/Carbon layer) which CANNOT be brought to Linux due to copyright issues, hence graphics is all thats left out and the one that can be ported to Linux which is what Mac4Lin tries to do.
Of corz, because of the way they things are structured in Linux its not possible to port over everything tho the quest to get that perfect setup is never ending.
A Mac OS X like menu bar can be gotten both in KDE (native support) and GNOME (thru GlobalMenu). I particularly do not thing menu layouts are wasteful (I work on all 3 platforms: GNU/Linux, Mac OS X and Windows). It all depends on your perspective.
When you say typefaces are bad by default, I sure agree with you.