This guy nailed it:

Blogger: Term used to describe anyone with enough time or narcissism to document every tedious bit of minutia filling their uneventful lives. Possibly the most annoying thing about bloggers is the sense of self-importance they get after even the most modest of publicity. Sometimes it takes as little as a referral on a more popular blogger’s website to set the lesser blogger’s ego into orbit.

Read more about bloggers and the blogosphere.