Don’t confuse a blog or Tumblr with a Microsite.

A blog or Tumblr is not a Microsite. A blog provides a vehicle for an organization or individual to communicate ideas and to experience limited interaction with the audience.

Blogs are great but extremely limiting. If you start to add secondary, informational pages to a blog, it’s a Microsite, which will likely require navigation — if not design as well — that’s different from the main site.