Koogle lamented that Internet companies had erred by giving away too much content to consumers in the dash to gain market share and notoriety. Consumers have been loathe to pay for any Internet content, from news bulletins to stock tips to downloadable music and software. The cool thing about my life is that I get to meet such smart people, and lots of the thanks for that goes to the Web. XML-RPC and probably SOAP could have happened without weblogs. Community projects require good communication, and the Internet, if it does anything, is an unprecedented communication enabler.
Mail lists are fine, but they can easily get locked up and frozen, unable to move.
Weblogs are different, it's possible on a weblog to speak and not give equal weight to every point of view. This begets more weblogs, giving people choices, they gravitate to the places that make sense for them. With this, movement can happen. Ask a question, get an answer, move on, ask another. After a few years, the results are visible.