WordPress just Released the the new version of WordPress 2.9 series, This is a very limited security update. It is mainly for multi-author blogs. if you have multi-author blogs then this is for you Update your Blog to latest version,
You must have already noticed the upgrade link but depending on where your server is, sometime you will only see the upgrade alert on your system hours later. Officially WordPress 2.9.2 is released to fix a problem about user permission in wordpress. As quoted on the wordpress blog:
Thomas Mackenzie alerted us to a problem where logged in users can peek at trashed posts belonging to other authors. If you have untrusted users signed up on your blog and sensitive posts in the trash, you should upgrade to 2.9.2.
As always, you can visit the Tools->Upgrade menu to upgrade.
