Wordpress rocks. I must admit I haven't tried any of the others but I doubt I ever will have the need to.
I just got through installing some of their plugins (
http://codex.wordpress.org/Plugins ) last night and I must say I love the Google Highlite (highlights the text in your blog that the surfer searched for from any of the big SE's, not just Google) and the Backup/Restore plugin (because I'm so paranoid about losing everything).