Just after I found an attack on my blog several days ago, miraculously it turns out that there was indeed a Wordpress vulnerability in v2.8.3 which caused me to take down the blog yesterday for a short amount of time. There have also been 2-3 patches for Wordpress in the last 2 weeks alone for other security vulnerabilities! 
You can read about it here:
http://wordpress.org/development/2009/08/2-8-4-security-release
UPDATE: This is actually quite a serious vulnerability, SANS explains it in-depth here:
http://isc.sans.org/diary.html?storyid=6934&rss
#1 by videolar on October 3rd, 2009
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Thanks a lot.Good idea..