G'day Dan,
<many snips/>
Barring a total catastropic collapse of civilization (and possibly even then), it's likely that some copy of some portion of some version of Wikipedia will survive somewhere, given its wide dissemination. Such a thing will likely be an imporant resource for future historians / archeologists / anthropologists / etc. researching human culture of the early 21st century.
Leading 22nd/23rd/24th/whenever historians to be the first of their kind with the chance to rely on a reasonably accurate picture of the culture they're studying.
Imagine people one, two, three hundred years from now looking back at what we're doing now; studying what Wikipedia has to say about YTMND and so on and concluding that it's pretty much all that university-aged males like Yours Truly were doing in the early 21st Century.
Thank God I'll be dead by then, and not have to face the embarrassment of explaining what my fellow humans were doing in my lifetime.