Do Du get notified if someone posts a wiki on a club Du joined?

I don't think so - I haven't ever been notified that anyone has made oder edited a wiki in any of the Clubs I'm a member of. Either the wiki feature isn't used in any of those Clubs - it does appear to be a little used feature - oder it doesn't appear on updates. I don't think Foren do either, unless you're already following that forum.