Yes I agree.
I am trying to integrate MediaWiki and BBPress and need to be able to define a main menu tab that is nothing more than a link to <site url>/wiki or <site url>/bbpress. In Mediawiki, at least, I can create a menu item that points back to wordpress. Although I haven't yet figured out how to do it from BBPress.
With these three programs, I already have a common user space. The next step is in solving the site navigation problems. After that, I will tackle common themes.
Yes, I realize that this brings WP one step closer to being a CMS. Is that such a bad thing? The CMS projects (Joomla, Type3, etc) are all stalling because they are trying to do (and control) too much.
Speaking of which,something like Joomla's menu management system wouldn't go completely amiss. But something that follows KISS a little closer would be good.