I think the lack of a notification to blog and forum comments and posting is a huge limitation. It makes the course a static experience. Like Moodle works great as a traditional start to finish course, but there is no way to develop any sort of community with this software.
Unless I missed something.
Someone makes a forum post and someone comments and they don't get a notification. Someone comments on a blog post and the blog poster doesn't get a notification.
I did vote on this in the tracker.