I've used wordpress, but every update changes the template system in a way that breaks it (so I've stopped upgrading, leaving my blog vulnerable..

)
tikiwiki allows you to setup user blogs, has built in forums, faqs, and a bug tracker (and of course a wiki). Their wysiwyg editor is fckeditor and it's pretty good.
To be honest, to avoid the whole mess of designing a site, I was thinking about setting something up on blogger recently... I've been thinking about doing a programming blog.
someone else on the forum might have more experience with blog software than me (Mathias has talked about blogging before if I remember correctly)...
qb