The technique is simply - open up a word document and begin to describe a type of reader that you’re either attempting to write for or who is already reading your blog. I’ll show you some examples of reader profiles that I have created below - but in short the task is to describe who they are, what their interests are, why they might be reading your blog and what their needs are.
via www.problogger.net
Here's an interesting post from ProBlogger regarding the use of personas (i.e. user profiles) in blogging.
We've been using this technique for a long time in web site development, albeit in a more formal form. User profiles can be a really valuable tool to use when planning, architecting and developing your web site. Contact us to learn more about this low-cost, high-return technique.
Lisa Kirschner
Founder and Managing Director, Flair Interactive Services Inc.
Managing Editor, Content 911 Blog