It's the fact that it's mostly-decent hardware running a mostly-compliant POSIX OS that looks enough like GNU to make it usable (and compatible with web servers).
If someone, ffs anyone, made a decent, reliable Linux laptop, Apple would lose the dev market in a month.
I'm running Debian on a Thinkpad at work, this work great... except for a few points.
It's always a bit harder to integrate with the rest of the internal infrastructure: * AD integration in your favorite email client to have auto-completion on emails is a bit tedious * Exchange calendars are also annoying * Mounting (and, first, finding) the windows shares can a bit tedious * Password renewal is not integrated that well
It works, but it takes a few hours to figure out and configure.
And sometimes you are just stuck with Windows/OS X because of a specific piece of software (for example in my case, the video conferencing tool we are using). I never used a truly Linux only environment in professional context, I always had a Windows VM also.
Indeed! The keyboard is amazing. The latest thinkpad x1 carbon is pure bliss, and Linux works out of the box for everything without any problems.
I share the frustration, mainly because both OS X and Windows are getting progressively worse over time as opposed to better, and the lack of a decent alternative is hugely frustrating.