I see everybody with the view that OSX is so much more productive, but I'll give a different view, as an OS X user turned Linux user. I switched entirely about 6 months ago, and it just sort of happened once Linux was set up to my liking.
Positives:
* Tiling WMs - I have always found myself working primarily in fullscreen applications like in OSX, but it's nice to have a small status bar at the top still and splitscreen capabilities. My WM of choice, AwesomeWM, provides this, and does it really well.
* Docker.io - Docker is infinitely better than Vagrant. It starts faster, it's thinner, and it's easier to interact with. And it only runs on Linux (at least for now, but it'd be hard to add OSX support probably, due to the use of cgroups and other Linux APIs)
* Better Package Management - Yes, OS X has homebrew, and it's great, but it has to compile from source, which takes a while and spins up your fans usually. It's just troublesome. And on Linux, if we want to compile, we can usually use distcc to distribute that load to a cluster. I do, and I know many others do as well.
* Choice of Workflow - OS X has a wonderful workflow, but it's not perfect. Sometimes it's nice to be able to pick the workflow that is almost exactly perfect for you, and tweak it until it's ideal. That's what I did, and it's been a huge boon for my productivity.
* Homogeneity with Deployment - this is a lesser positive, but it's still nice in many cases. Most of the good distros will teach you at least basic sysadmin skills over a shot period of time, through immersion. This means you can spend less money on sysadmins and do it yourself as long as possible, assuming you deploy on bare EC2
Negatives:
* More downtime - this is an issue with distros like Arch and Gentoo, and it does get to be a problem from time to time. I mean, it's hard to work when X11 won't start or a driver is broken (I'm looking at you, Broadcom)
* Learning curve - Linux really is as hard as it seems to learn, I'm not gonna lie. It's not perfect.
* You look like an "Engineer" not a "Hacker" - Lots of people will view the fact that you spent time customizing your work environment as you playing around with your OS. It's not really that way (unless you're a Gentoo user) but it gives that view to some people.
* Lack of support for multitouch trackpads - I'm sure this is less of an issue for other people, but it really was a dealbreaker early on for me. It killed all the ways I interacted with OS X. It was terrible for a while, then I got over it.
Honestly, I dual booted Arch and OS X for about 8 months before I ended up tipping over to Arch. It took me setting up a shared partition and AwesomeWM before I could convince myself to use it daily. But it's the best decision I've ever made, because I find myself being infinitely more productive with my new workflow. I'm done with OSX entirely, I only use it for Photoshop now.