Ok, the reason this is happening is due to an account being required to post a comment on your blog.  We've changed things so that when someone tries to add a comment (by clicking on the link) and they're not logged in, it will prompt them to create an account or to login to their existing account. 

As far as showing comments on the blog home page, I'm not so sure about this as it could fill up your entire blog's home page with comments - which might not be so great for a blog.  However, some solutions around this would be promoting links to the individual blog posts, where the comments will be shown.  Right now we're looking at adding Facebook/Myspace integration which would post a direct link on your social network of choice whenever you post a blog entry (as an option).

Hope this helps!