Disqus: A comment system or a new type of blogging?

Disqus is a new comments system for blogs. So what's the big deal?
Well, Disqus may change the role of blogs as we know them. Here is what it does:

• It provides threaded conversations and encourages people to participate and to use their identity (see picture below)
• Every commenter has a profile that is used on all blogs enabled with Disqus.
• People can track, follow and rate other peoples comments.

So why is this important? The implication of this new approach is that it moves the center of gravity from the blog post to the comments and from the blogger to the community. Comments are not isolated anymore, but they form active conversation among users.
So, if I am a reader and all I do is go from blog to blog and leave cool comments, all these contributions will be automatically stored in my Disqus home page. Other people can comment or /rate my comments, and can decide to follow me.

So the big question is: do I still need to blog or can I replace blogging with commenting?