This is interesting. A few minutes into this Scott Hanselman makes the point that “all professional developers should have a blog”. Some of the benefits specified were that it exercises your brain to write better documentation, and it reduces your typing as you can put something in one a blog and you get to more people. All this knowledge is in our head, and if we put it in an email, then we simply waste it (and probable then write it again later!)
Suggested listening material!