AVERT Labs - Excellent Diagrams on new DNS dangers
The diagrams in the link below are excellent in showing how DNS resolves canonical names to numerical IP addresses, and how the bad guys can potentially manipulate these with the new exploits. Most vendors now offer security updates for DNS and these should be applied as quickly as possible to better protect corporate Internet applications and customer information (e.g., especially from potential phishing attacks).
http://www.avertlabs.com/research/blog/index.php/2008/07/23/the-cat-is-out-of-the-bag-dns-bug/