Specifically, why is it so important to predict the doom of Google's "Don't be evil" culture (arguably the best piece of marketing since Nike's Just Do It or something similar) or why is it so important to predict the doom of Wikipedia? More than 1 million articles exist, close to half a million in the English edition alone. Lookups related to current events get grafted onto the encyclopedia at a pace no established coherent source can match.
Sure there are quality problems, but come on. By any standard, the speed with which this volume of data got assembled, at the level of quality that it does actually have, is remarkable.
The latest batch of attacks are reruns of a round of "But, but, it's written by pimply hackers, not experts" attacks of a couple of months ago. I think the attacks are disingenious. First of all, in fields where experts embrace The Reputation Economy wikipedia is pretty damn good. As an example, I'd have to say that the mathematical material in wikipedia is much better than the material in any general reference I use.
Phenomena like blogging means that more and more people, from a broader and broader range of fields, get a feel for how reputation works online, and as they get comfortable with blogging they will also get comfortable with something like Wikipedia. Needless to say, wikipedia has trouble in fields that are tradionally mastered by old guys in tweed jackets - classical literature, some elements of history, classical music etc.
The prediction of imminent doom is really a theme in present day culture. I'm sure that means something (in fact my brother may just have written a book (in Danish) about it).