How to Secure your WordPress blog Against Hacking?

WordPress users warned of hacking worms! Recently, WordPress founder Matt Mullenweg has posted an article about keeping your WordPress installation safe. It discusses a worm which is targetting older versions of WordPress by creating a “hidden” admin user. The attack affects only self-hosted versions of WordPress (wordpress.org), not those at WordPress.com. The solution to avoid being attacked, if you have not done so already, update your WordPress install immediately to the latest version. Keeping your WordPress up to date is "taking your vitamins; fixing a hack is open heart surgery". There are many WordPress security plugins you can use to secure your WordPress blog/site, but the essential thing you should not forget is upgrading to the latest version!

Quoted from WordPress Blog. How to Keep WordPress Secure by Matt,

...WordPress is a community of hundreds of people that read the code every day, audit it, update it, and care enough about keeping your blog safe that we do things like release updates weeks apart from each other even though it makes us look bad, because updating is going to keep your blog safe from the bad guys. I’m not clairvoyant and I can’t predict what schemes spammers, hackers, crackers, and tricksters will come up with with in the future to harm your blog, but I do know for certain that as long as WordPress is around we’ll do everything in our power to make sure the software is safe. We’ve already made upgrading core and plugins a one-click procedure. If we find something broken, we’ll release a fix. Please upgrade, it’s the only way we can help each other.