The arguement against Linux that bothers me the most is the one that states that inexperienced users just can't handle the change away from Windows or some such. In my opinion, the only thing holding these users back from learning Linux is an unwillingness to learn. If they're willing to learn, then the transition is no problem at all. If they're not, well, they'd be happier sticking with Windows anyway.
To illustrate, I'll talk about a couple of my own experiences. The first of these was when my wife bought a Macbook Pro (I know, still not Linux...) to replace her Windows laptop. My mom was interested in getting a laptop, so we sold her my wife's old one. When we gave it to her, she was rightly concerned as to whether it had all the proper antivirus, antispyware, and firewall software on it. After assuring her that it did, I told her that for what she uses a computer for, I could install Linux on it and she wouldn't need the antivirus and antispyware, and that she'd still be able to do what she needed to. She was apprehensive to learn a different way of using the computer, so she declined and told me that XP was fine. It's not that she's afraid of technology--as a high school librarian, her library was one of the first in the area to switch to computerized records back in the day--but she was comfortable with what she had.
In contrast, my wife's cousin came over a few months back, and was intrigued at the strange-looking (Gentoo running Gnome) desktop on my computer. I told her what it was, and proceeded to show her stuff like Compiz, multiple workspaces, installation of programs from the repo, and the like: stuff that Windows couldn't offer. She really liked what she saw, and was particularly impressed with Conky, so I asked her if she'd like me to install Linux on her computer. She didn't like the sound of it, but I gave her a couple of live CDs for her to try out. I figured that she wouldn't want to make the switch, but hey, I could take the loss of a few CDs.
The next time my wife's cousin came over to babysit, she asked me if I could "install that program" on her computer after all. She complained that Vista was too slow on her computer, and was frustrated with its byzantine UAC and configuration tools and such. After confirming that "that program" she referred to was Linux, I happily went about installing Ubuntu 9.04 on her computer. (Yeah, I know, but Gentoo would have taken too long to install, and probably wouldn't have been an ideal distro to learn the basics with.) Unlike my mom, she was interested in learning, watching me go through Jaunty's installer and asking questions about what I was doing. She was impressed that Ubuntu installed so quickly, and was eager to get into using it when the install finished.
After she did the post-install setup and played around with Ubuntu for a while, I offered to customize her install to make the adjustment from Windows easier. As much as I respect the free-as-in-speech aspect of Linux, I find it difficult to run an OS of the likes that the FSF would approve of. I imagine that my wife's cousin, being a typically-connected teenager, would find it difficult as well given that she listens to mp3s, visits YouTube, watches DVDs, and the like. Moreover, since I left Vista on her computer in case she wanted or needed to boot back into Vista, I thought I'd set it up so the NTFS partition was automounted, and then symlink her "Music" and "Video" folders to their respective locations on said NTFS drive so that she'd have access to her existing collections. So, I fired up the terminal and went to work. She was still interested in knowing what I was doing and why I was doing it, and surprisingly, she was fascinated with the command line and wished to learn how to use it. She described it as something like "It's so cool, like you're talking to the computer!", which I suppose is pretty accurate. So much for the old myth that new users don't want to use the command line, too.
After I finished installing the freedom-hating codecs and setting up /etc/fstab and installing a few miscellaneous programs (including Conky!), I set her free to explore her new OS. She quickly took off, and by the time I looked at her screen again, she'd customized the theme from orange to green, set her own background, and done a few other things to make Ubuntu her own...none of which I'd showed her; she'd figured them out herself. My wife's cousin hasn't come to visit since then, but I'm curious to see what she's gotten up to with Linux since then.
I'd say that both my mom and my wife's cousin have comparable levels of computer knowledge, and they use their computers to do much the same thing. The difference between them, though, is the desire to learn. With such a willingness, my wife's cousin had no trouble adjusting to Ubuntu. Granted, I installed it and set it up for her, but if I had been installing Vista out of the box on her machine, I'd have had to do similar setup as well.
So is every inexperienced user ready to switch to Linux? No, but it's not because Linux is arcane and difficult to use, it's that the user has to be willing to try something new.