Granted that's what games are about. But gamification is about using game mechanics (mechanics being things like -scores- which let you understand your position against that position of other people, and rules, which keep you from doing whatever you like, as something completely aside from the point of the 'fun' of the game) to do something much more functional than make things fun: to make things addictive or otherwise drive the user to pursue things outside of their standard pattern.
Stack overflow's design isn't about making it fun, its about making the users collaborate into something that is easy and valuable to the population. The rules of a game in general aren't about making the games fun, they're about providing a framework for competition.
Right, and that's why I think "gamification" will be a fad. Eventually people will see through transparent attempts to lead them by the nose through otherwise completely unengaging content and will move on to something more compelling.
Sure, designers will continue to include game mechanics to enhance engagement, it just won't be this crazy concept that everyone obsesses about. It'll just be a tool you can use sometime if the situation seems right.
And I disagree about stackoverflow on both counts. I believe it is fun, and that competition is a nonessential component to the sites success. Some people do thrive on competition, others do not. The core of stackoverflow is the dialogue between askers and answerers. Maybe say "rewarding" instead of "fun." The scores and rules are a nice enhancement to the core experience-- they facilitate public recognition, sorting and organization, among other things. There has been competition and recognition on Wikipedia for a long time, and they have made no overt attempt to "gamify".
Another important thing that the stackoverflow game mechanics do is guide users to functionality they might not know about. What you call "driving" users I would call "leading." Hardcore completionist, achievement-oriented, and competitive users are, of course, driven. The rest, however, are not, and to them features like "badges" just bring attention to the wide variety of ways the site can be engaging. The FAQ is well-written and very useful. The "analytical" badge merely helps draw a little extra attention to it. vBulletin has a boilerplate FAQ that probably no one has read in years since it's the same on every single forum that uses the software.
Stack overflow's design isn't about making it fun, its about making the users collaborate into something that is easy and valuable to the population. The rules of a game in general aren't about making the games fun, they're about providing a framework for competition.