I developed for several years solely on a Linux laptop - it was my personal laptop too. Then I switched to OSX, and damn what an awesome breath of UI fresh air.
I would never deploy anything on any platform besides good-old Linux, but for a personal computer, I'm sold on OSX.
I hate to turn this into an OS debate, but it looks like it has become one. I have used OS X. I have written software for OS X. I had a job that was to support OS X.
I don't like it; I don't think it works well. It doesn't do what I want and it's not particularly stable. Problems I have with OS X are nonexistent with Linux, so that's what I use.
I have used Linux since 1994. I have written software for Linux. I had a job that was to support Linux. I still run Linux on servers where there's no other option.
I don't like it; I don't think it works well. It doesn't do what I want -- the desktop software options are incredibly lacking, getting anything working is like pulling teeth, and relying on a distributor like Debian or Ubuntu for all my software means that I get stuck either using outdated software or running against an unstable release of the OS -- either way, I spend way more time thinking about the OS than doing my job.
In terms of stability, the lack of stable releases, poor code quality of the kernel, and reliance on distributors to patch and maintain their own kernels really shows through in the number of kernel panics and other issues I see. I can't recall the last time one of my FreeBSD servers or Mac OS X desktops crashed.
Problems I have with Linux are nonexistent with OS X, so that's what I use.
Yes, the Linux kernel code quality is low, and things often regress. C + no unit tests + opinionated dictator with very little computer science experience = very, very bad. But it works well enough. As long as you are on the beaten path, with Intel hardware and Nothing Too Weird, you will be fine. On OS X, you don't even have the choice to even try anything else.
As for the distribution issue, it's true that you are either out of date or slightly unstable. But on OS X, you can't get any packages at all. So you manage everything yourself, or rely on a third party to package everything for you. Then you are out of date or unstable, and the various package managers conflict with each other and with Apple's stuff. There is no magic fix there, it's the same set of problems.
So anyway, I don't care what OS you use... but OS X is not objectively better. (I have noticed that OS X users prefer no way to do something over a flaky way to do something. Linux has a lot of flaky ways to do a lot of things; OS X just doesn't do much. Tradeoffs.)
I would never deploy anything on any platform besides good-old Linux, but for a personal computer, I'm sold on OSX.