I didn't see an announcement on the Macromedia DevNet DRK site yet, but when I logged into my subscription tonight, DRK 8 was available for download. Here are the CF highlights incase you can't wait for the official release...

• New forums application by Ray Camden
• Assert API - Custom tags for adding special checks in your code.
• WSDLerator - Tool for discovering and testing Web Services for use within ColdFusion.