From my perspective, there is little difference between the various flavors of Unix and Linux that I have used. So far, I have experience with Red Hat and Debian Linux, HP-UX, and Solaris. The main differences that I have found deal with command-line options for tools like tar, make, ps, ls, etc. For example, on my Debian system at home, I can type
tar -czf filename.tgz *
To create a zipped tar file. However, on the Solaris systems on campus, I have to do
Solaris has a number of features appropriate to large servers running with load balancing, but commonly-used commands reflect Unix about 10 years ago. Or at least Solaris 8 did. I haven't spent enough time on 10 to pay attention.
In general, the Linux versions of these same commands have more amenities.
However, there's no "one" Linux (well, discounting what you get from kernel.org). RedHat and Debian stow distro-specific config information in different locations.
One thing I do appreciate about Linux over older Unixes is that the /etc directory is amost entirely text files, and they don't keep executables in it. Much tidier to maintain and manipulate.
Customer surveys are for companies who didn't pay proper attention to begin with.
I think that, in his own unique way, Michael was trying that Linux seems to have a large following among power users. In the United States, someone that knows a lot about computers is often referred to by various slang terms: nerd, dork, geek, etc.