For a Long Time Now...
My first Linux experiences come from RedHat 5.1 (No, not RHEL 5!) back in '97. I still have the box with the floppies, book and CDs.
It wasn't my first experience with *nix. I started with HP-UX for work, SCO unix at home (since that was the only reliable and supported available on i386-platform) some years before that. People thought of me as crazy back then. Most even had the stupid old-fashioned idea I should be at home, having children instead!
After RedHat, I tried many other distributions and what struck me early on (and still applies) is that some distros run better on certain hardware than others. Some install like a breeze, others require days of fiddling and tweaking on one machine, whilst it might be the reverse on another.
A good example is Ubuntu 5.04, that one didn't want to install and consequently run on my Acer Ferrari laptop (the 2003 model), whilst Mandrake seemed to recognize the machine perfectly and everything worked straight away.
Then there is also the choice of what you want to do with it... Some distros are excellent for graphical applications, where others are better at audio.
I don't like people bashing one distro for another or windows, or MacOS. Each distro serves some people, it's sometimes a choice, sometimes a necessity. Sometimes we're tied into an application that just doesn't want to run on anything else and there are no viable alternatives on another OS.
A good example is my Eee PC, most distros focus on being connected, some even specialize in it, like Moblin. I prefer something a bit more balanced, Ubuntu Netbook-remix or something alike (as I mentioned before, currently EasyPeasy).
Most my machines run a distro of linux, I even have one dual boot for the winblows environment (yes, I like to play BurnOut: Paradise sometimes and that one doesn't run on my SuSE installation).
I'm mostly on the shell, when I'm on my main PC, I tend to have many ssh-connections open to my linux machines... My heritage is commandline, I'll never be a window-person. (Not the OS, I just am not a fan of GUIs).
What I like most about linux is the stability. If you have the right distro running on your machine, it's getting close to impossible to bring it completely down. Unlike windows, one bit falling over and you get a blue screen of death. Yet we stick up with it, since we don't have a full choice.
Thumbs up for the collective collaborations that result in linux environments!!