I set up my first tumblr account today. I also wrote an article about Firefox Aurora today. 

Which got me thinking. I already have Facebook, Media Hack, Media Hack on Facebook and Twitter, so why Tumblr? 

Using a crude variation of the Mozilla classification:

• Tumblr is the pre-release (mostly unstable, prone to random thoughts) release;
• Twitter is for the partly-polished ideas;
• Facebook is for internal communication; and 
• Media Hack is for things I feel ready to share properly with the world.