As I woke up today, I saw a notice on my dashboard asking me to upgrade. Like always, I looked at what it is. Turned out that last night, WordPress team released a security and maintenance update. WordPress 3.3.1 is here, and we urge you to upgrade your sites. This maintenance release fixes 15 issues with WordPress 3.3, as well as a fix for a cross-site scripting vulnerability that affected version 3.3.
Are you one of the curious ones who want to know what changed? Check out the changelog.
I will keep it short and simple.
Upgrade now 
Syed Balkhi
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Prajwal
Good update!
technomaz
thanks
Sean 'Wordpress Guy' Vosler
arg, so many sites to update! lol