http://lastwatchdog.com/driveby-downloads-lurking-8-million-small-ecommerce/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+LastWatchdog+(The+Last+Watchdog)&utm_content=Google+Reader
Interesting article on the dangers of not keeping software patched, particularly with regards to open source content management systems.
http://www.seobook.com/wordpress-blog-hacking-checklist
Tips on how to both detect WordPress hacks and more importantly, prevent future hacks.
http://www.wolf-howl.com/blogging/wordpress-clean-backend/
A list of security related plugins for WordPress. Some good stuff.