Today is all about determining who your target audience is. I use Clicky (it's free) to see my demographics but you can also use Google Analytics or Alexa. It's important to know who is visiting your blog so that you can curate your content to their preferences in order to keep them coming back. You can also use the responses from your reader survey in order to determine what you readers like. Reader surveys are also good for finding out what your readers might like to see more or less of or to find out about things they would like you to change.
Who is your target audience? Did you intend to have that audience or were you aiming for someone different?