If you want to keep up with the latest in web application security, you might want to add Planet Web Security to your reading list. In his announcement, Christian Matthies offers this brief description:

I am pleased to announce the launch of Planet Web Security, founded with the intention to bring together similarly themed news and rants related to web security and to display them in one place.

It's still in its infancy, so I'm sure it will only get better as more relevant blogs are added. Comparing it to my own planet (not specific to web application security), I can already identify a few blogs that should probably be added:

• Andrew van der Stock
• Anurag Agarwal
• Dan Kuykendall
• Ed Finkler
• ModSecurity Blog
• Nitesh Dhanjani
• OWASP Blogs
• Ryan Cartner
• Shreeraj Shah
• Sylvan von Stuppe

Congrats on getting this launched, Christian!