I learnt Swift last year - now my brain is better.
Fitting the slender demographic of mac owning old crusty unix hack with enough time on hands for something new, last year I chose to learn Swift. Coming from a Perl and C background it has taken a while to get head round objects and iterators but I now really like the newish language. I can really see how this modern language has made it possible to build more robust software from the ground up. Like INGSOC (from 1984 (the book by G. Orwell)) the language is structured and typed enough to remove dangerous (index out by 1) faults and common runtime problems. On the native Mac it has a low barrier to entry being usable for cmd line scripts without pre-compilation or linking and gives out helpful error message on parse failures. Good on-line documentation and tutorials available for free.
Once off a Mac things do get tricky, Ubuntu installs are available, one right from the App Store, but they lack the support libraries for GUI building and multitasking and toolchain seems rather fragile and version sensitive.
Overall a great language that has built on the best bits of older languages but may end up as the next Pascal.
PS: Yes I mostly edit the src in Vim with colour coding package added but sometimes wander over to the Xcode dark side.