nmap 6 was released earlier today, which is a major upgrade to the old version of nmap. One feature that excites me in particular is "full IPv6 support", including OS fingerprinting. 

In order to efficiently scan IPv6 networks, nmap added multicast requests to enumerate live hosts on a network.

For more details, see http://nmap.org/6

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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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