Thursday is Blog Action Day.

What the hell is that? Glad you asked ...

Blog Action Day is an annual event aimed at uniting the world's bloggers in posting about the same issue on the same day. Their goal: To raise awareness and trigger a global discussion.

This year's topic? Climate Change.

So far, almost 6,000 blogs are registered from 126 countries. Change.org, the event's sponsor, estimates the group's blog posts will reach nearly 11,000,000 readers.

In case you're wondering: Here's a list of participants and here's a list of sponsors.

If you decide to participate, make sure you tweet your posts with this hashtag: #BAD09.

Don't want to blog, but still feel the need to be heard? Here's a list the group compiled to help you get started.

Now, here's Blog Action Day is all about:

First and last, the purpose of Blog Action Day is to create a discussion. We ask bloggers to take a single day out of their schedule and focus it on an important issue.

By doing so on the same day, the blogging community effectively changes the conversation on the web and focuses audiences around the globe on that issue.

Out of this discussion naturally flow ideas, advice, plans, and action. In 2007 on the theme of the Environment, we saw bloggers running environmental experiments, detailing innovative ideas on creating sustainable practices, and focusing their audience's attention on organizations and companies promoting green agendas. In 2008 we covered the theme of Poverty, and similarly focused the blogging community's energies around discussing the wide breadth of the issue from many perspectives and identifying innovative and unexpected solutions. This year we aim to do the same for Climate Change, an issue that threatens us all.

From the smallest online journals to huge online magazines, Blog Action Day is about mass participation. Anyone is free to join in on Blog Action Day and there is no limit on the number of posts, the type of posts or the direction of thoughts and opinions.