The community-driven content of Web 2.0 has had a long run, and it surely isn't going anywhere. It's achieved some truly amazing things: who would have thought, even one generation ago, that today we'd have information sources like Wikipedia, or that they'd be as good as the best of them really are?
However, Web 2.0 has also shown us the weaknesses of a system where all voices are equal regardless of knowledge or experience. It has proved surprisingly difficult to create and sustain self-moderating communities that function as meritocracies, both in terms of the accuracy of information or validity of advice, and in terms of the challenging legal and ethical questions when one possibly anonymous person's free speech butts up against the real and possibly serious consequences of what is said for someone else. That same Wikipedia has had entire long and well-established pages on subjects where the content was utter drivel for months or years at a time, because it was utter drivel that enough inexperienced people believed, and there was no effective mechanism or incentive for a real expert to set the record straight.
It seems likely that many of these issues could be overcome if we combined the undoubted enthusiasm of the masses for having their say with a greater amount of input and influence for real experts and diligent moderators. However, that probably requires giving up a degree of the anonymity/pseudonymity we enjoy today, which does usefully allow for more honest and open discussions at times, so that credibility can be established with sufficient transparency to generate trust. It probably also requires people to actually pay real money to support the content or offset the running costs of discussion forums, so that a greater degree of expert contribution and/or moderation is actually viable without relying on ads, affiliate marketing schemes, or other secondary revenue sources that cloud the issue. That in turn may well require some form of either micropayments or syndication, and whoever cracks that one is probably the next Stripe.