pros:
Customizability - uninstall what you don't need, which can make your machine dedicated to the task you want it to do, running the necessary software only. In the win/osx case you can only add/remove programs, while the 'core' bloat stays. This leads to another 'pro' - speed.
Speed - because of the lack of bloat on the system (to which win/osx users are used to already) and the possibility to configure it exactly the way one wants/needs.
Learning Opportunity - because of the knowledge one gathers even by just trying to get along, most of the time without eve noticing. Like it or not, you get more expert-level knowledge on the basics and the way the normal computer works etc. which can eventually lead to a more computer-literate population.
Free (in any mean) - this might be the greatest 'pro' which also leads to a significant 'con'...in the 'cons' part.
Stability - it's not a surprise at all to see a tux machine with uptime > 1000 days. Win system can withstand not more than a week. Even with no viruses/regular updates. In most cases, some of the programs on the machine simply stucks and of course, the whole machine needs a reboot. My experience, at least. I can't really discuss any similar experiences with osx.
cons:
Learning Curve - even though a BIG pro, there are users that consider it a con. Some (plenty??) of the users just want the computer to run and for them to just click on the mouse and not have anything to do with it's errors and log files, numbers, dots, colons and semicolons.
Interesting, but I've engaged this discussion couple of times, and I've found that plenty of windows users find rebooting a machine the perfect answer. Even if you try to explain that only one look at the log files can tell you where the issue is and which exactly service needs an attention, you get head nods in disapproval usually followed by a 'too complicated' comment. It might sound like I'm bashing those users, while in fact, I completely understand and to some extent justify that attitude - not everyone can or wants to do it. Not everyone has the time or the will to.
Free - why a con? It's free, which means noone is particularly interested in advertising it or engaging a marketing campaign (or at least one as
loud as Microsoft's or Apple's), so everyday people watching TV and surfing all day long have mostly heard of those two names.
p.s. Yin, Yang, Tux is the name to go
Thanks for the post, excellent idea.