Currently, Haus News it the blog located at the front of http://blogs.codehaus.org/. Once Confluence supports categories, we'll probably retire MovableType entirely. But until then, we're stuck with it.
When you make a release, specifically. If you post a blog entry to the Releases category, it'll appear on Releases and also be aggregated on JavaBlogs. It'll also appear on the front-page of the HAUS site.
You need to
activateblogaccount and then surf to http://blogs.codehaus.org/mt.cgi and login. Should be self-explanatory after that.