I am also curious what are objective reasons to use OS X (apple laptops) over Linux for code developers?

For code developers Linux is better, it's free and open, all sorts of trendy things more convenient to test and use on Linux, there is everything could be configured (and you will have to configure everything :)) Even for not code developers but picture/3d it's better to use laptops with pro graphic cards (FirePro/Quadro) than apple laptops. Also OS X is proprietary, so if you are conspiracy theorists it's probably not the best choice.

Currently I'm using Dell E7440 (FHD IPS screen (no touch) and SSD is essential) and Arch linux + Gnome shell (there is also win 8 as second system, just for case), and I'm happy so far.