@ Benny

Not only integration in that sense. The interface is coherent. Its object oriented, so e.g. interfaces and shortcuts are coherent. If I ask you what F5 and F7 did in DOS applications I know what your answer will be. Sure, Windows and open source DE have this too, but Apple takes this one step further. There are some nice NextStep/OpenStep/GNUStep demos which demonstrate this.

Something else the iPhone does right is allowing full screen focus to the user. Wayfinder/Navicore, Carman, OMWeather, Fennec and some other applications do this as well; but definetely not all.

An abstraction API for Google, Facebook, etcetera which can be used by an application such as Pidgin plugin as well as Bitlbee, a blogger program, or a Firefox/MicroB/Fennec extension is a Good Thing.

If you want sexy and good performance you can learn from Enlightenment DR17. If you'd study that community you'd notice how they care about optimizing and how these people are artists (besides being programmer), and have a hard time releasing a stable

XFce wasn't mentioned, but they go more for performance than GNOME. Yet, you can see the 'Mac' influence in both.

(Please note there are also influences by e.g. AmigaOS, BeOS, NextStep; its just that Apple has survived whereas these OSes either vanished or got cloned or integrated into new products.)