I’m increasingly thinking that the right approach for internets is a mix of documentation management (pdf/doc/xls), web DB apps, wikis, mailing list repositories, internal blogs and most importantly independent index+search technology to tie it all together.

Using only one of the technologies invariably leads to it sometimes being the wrong tool for the task and the default search of any tool always sucks because it isn’t dedicated to search.

if you can get people to use them

Independent of the medium (newsgroup, blogs, wikis), I suspect this is the perennial, deep seated issue. Things may change but I doubt I'll be alive to see it.