Hard works from the staff preparing Wordpress 2.9 stable version. In the while it's possible to test the beta version
A worm registers as Wordpress user, makes itself admin and inserts hidden spam and malware in old posts.
An overview on Wordpress functions references for developers, including core functions and Template Tags.
1 Blog Theme is a popular Wordpress Theme written and developed by Javier Garcìa.
An interesting list by 1stWebDesigner of tricks and hacks with new 2.8 Wordpress version.
A very useful plugin to check broken links in posts, pages, blogroll and (optionally) custom fields.