Blogging has not peaked, it's just morphed into something else and has taken a different form (and will continue to do so) respect of the original concept of a blog.

Also, take into account the difference between “journalistic/trade/opinion” bloggers versus the 'OMGZ! Sanjaya is awfulz!' bloggers. My bet is that the amount of 'personal' bloggers is dying off as they move to social networks laden with RSS and other types of blog-like CMSes. So, blog consumption and usage has merely changed, morphed and evolved, not peaked.

The more people begin to blog, the more interesting conversations can take place. With this being a tool that can lead to dialogue vs. pushing content through, we are often engaged in writing thoughtful comments as well.