But, I grew tired of Finder, of spinning beach balls, eye candy, manually resizing windows, and generally mouse clicking around what more and more seemed to me like a McMac than the world's greatest OS.
What kills it for me on Linux are the tiling WMs. Try Awesome or i3, absurdly good user experience (using the latter here), particularly in a multi-head setup. Have about 15 terminals open here on one monitor, snapped into a quadrant grid with each panel consisting of a few sub tabs. No mouse needed, no manual resizing nonsense, no cluster fuck of randomly layered windows to sort through.
Throw in an expose-style docker for Skype, Rhythmbox, Gnote, etc. floatable apps and you're golden.
Love me some Linux, only point of OSX is to fire up a VM and see how my web apps look on the iThings in Xcode hardware simulator ;-)