Good article about books vs. the Internet that makes a point that is relavent to the FOC08 Facilitating Online Communities discussion.
John Hagel says, "tacit knowledge will only flow through shared practice and the deep relationships that build up around shared practice. Some examples of shared practice can already be found on the Internet in such diverse arenas as open source software and online games like World of Warcraft. This is one more area that the Internet will likely evolve to support much more effectively in the years ahead."
Online communities and the technologies to support them are evolving. What we know today is rapidly changing. This will have a profound impact on the nature of online communities and how they are "facilitated" - assuming that's the right word for what we are doing.