Late Monday afternoon Apple released updates to Snow Leopard and Snow Leopard Server, and a security update to Leopard 10.5.8. Below are links to Knowledge Base (KB) articles listing details on each update.
Snow Leopard 10.6.2
KB Article
http://support.apple.com/kb/HT3874
Snow Leopard Server 10.6.2
KB Article
http://support.apple.com/kb/HT3875
Mac OS X 10.5.8 Security Update 2009-006
KB Article
http://support.apple.com/kb/DL963