For several years, Ubuntu has been synonymous with user-friendliness. A Web search quickly unearths dozens of articles that suggest that Ubuntu is the distribution you should give non-technical people to introduce them to GNU/Linux. It even won a "Most User-Friendly Linux Distribution" award, which you might think confirms its status.
However, like all conventional wisdom, this association is worth exploring. For one thing, you have to wonder whether comparisons for user-friendliness have any relevance in free and open source software (FOSS). For another, what exactly are the characteristics of user-friendliness? Moreover, does stressing user-friendliness mean ignoring other values -- perhaps equally important ones?
Comparisons in FOSS
One problem I immediately have with titles like the "Most User-Friendly Linux Distribution" is that they seem more a ploy for commercial marketing than anything that applies to the world of FOSS development.
These comparative claims make little sense in FOSS in that -- as anyone who has tried more than one distribution can tell you -- much of the user-experience is determined by the desktop. Distributions play a role, of course, in assembling the selection of software and making sure that everything works together. However, for several years now, Ive seen more innovation in the form of new applications and features in releases of GNOME or KDE than in any distribution. For the casual user, the difference between Ubuntu and any other distribution is fairly minimal, and often more a case of finishing details than of functionality.
Even Ubuntu's forums and online documentation, although specific to the distribution, are usable by those working with other distributions. The documentation on wireless cards, for instance, is not only clear and concise, but useful for almost any GNU/Linux, regardless of their distribution.
Just as importantly, so far as distributions do innovate, any claim that they are ahead of others is going to be true only for a brief while. Improvements in one distribution are likely to be mirrored by other distributions within a few months, either through re-use of the code or through stimulus diffusion -- developers hearing about an application and writing a version of it for their programming tool kits.
For instance, when Fedora came out with Smolt, a tool for reporting information about the hardware on which the distribution was installed, Ubuntu soon came up with the equivalent in its Hardware Testing application. No doubt in other cases, Ubuntu was first.
This exchange of ideas is especially strong in Ubuntu's relation with Debian, the distribution it derives from. Ubuntu borrows many packages from the Debian unstable repository, and, in turn, many of its innovations are returned to Debian. In fact, a number of Ubuntu developers are also Debian developers. The relations between the two distributions are sometimes testy, with some Debian developers inclined to feel that their counterparts in Ubuntu don't share freely enough, but the inter-dependence remains.
For such reasons, most of the differences between user-friendliness in the major distros seem minimal. Remembering just when each distribution added which feature is almost impossible, but, so far as I can recollect, few of Ubuntu's features are unique. Yes, it helped promote the use of assistative technologies and internationalization features such as SCIM, which switches keyboards on the fly. It also helped to popularize the use of Live CDs so people could see Ubuntu without making changes to their computers.
But such features are not unique to Ubuntu. You could have the same functionality in many other distributions -- but the difference is that you would have to install them and work out any problems. Ubuntu's accomplishment is that its developers realized that such features should be part of the same default installation, not that they did anything resoundingly new.
What does user-friendliness mean?
Another trouble with describing Ubuntu as user-friendly is exactly what you mean by the term.
If you mean simplicity of use, then Ubuntu deserves its reputation. By default, Ubuntu boots without displaying messages. It installs with equal simplicity from a Live CD -- although an alternative installation program with more detail is available for experts. Similarly, its default desktop reduces the virtual workspaces to two (enough to give users the idea without overwhelming), and presents a menu bar carefully designed to give uses a tool in each major application area rather than to display all the software installed, the way that more traditional distributions like Debian do.
However, simplicity is a two-edged feature. On the one hand, each of these choices can be condemned for hiding complexity and keeping users stupid, but, on the other hand, they also help to ensure that new users in particular aren't stricken with option anxiety and flee GNU/Linux whining that it is too complicated. You might say that Ubuntu is user-friendly in the short-term, but less so in the long-term, since it does not provide much in the way of guidance for users who want to progress beyond the basics.