Nothing else to say that's in the announcement:

At this time 6.4-RELEASE is expected to be the last of the 6-STABLE releases. Some of the highlights:

• New and much-improved NFS Lock Manager (NLM) client
• Support for the Camellia cipher
• boot loader changes allow, among other things, booting from USB devices and booting from GPT-labeled devices with GPT-enabled BIOSes
• DVD install ISO images for amd64/i386
• KDE updated to 3.5.10, GNOME updated to 2.22.3
• Updates for BIND, sendmail, OpenPAM, and others

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