From the release announcement on http://nmap.org:

"The Nmap Project is pleased to announce the immediate, free availability
 of the Nmap Security Scanner version 6.00 from http://nmap.org/.
 It is the product of almost three years of work, 3,924 code commits,
 and more than a dozen point releases since the big Nmap 5 release in July
 2009. Nmap 6 includes a more powerful Nmap Scripting Engine, 289 new scripts,
 better web scanning, full IPv6 support, the Nping packet prober, faster scans,  and much more! We recommend that all current users upgrade."

Here is a condensed Changelog:

Nmap 6.01 [2012-06-13]

o [Zenmap] Fixed a hang that would occur on Mac OS X 10.7.

o [Zenmap] Fixed a crash that happened when activating the host filter.

o Fixed a bug that caused Nmap to fail to find any network interface when
  at least one of them is in the monitor mode.
  http://seclists.org/nmap-dev/2012/q2/449
  http://seclists.org/nmap-dev/2012/q2/478

o Fixed the greppable output of hosts that time-out.

Nmap 6.00 [2012-05-21]

o Most important release since Nmap 5.00 in July 2009! For a list of
  the most significant improvements and new features, see the
  announcement at: http://nmap.org/6

o Some XML output improvements...

o Lots of NSE scripts added and updated...

o Fixed the routing table loop on OS X so that on-link routes appear.

o Upgraded included libpcap to version 1.2.1.

o Fixed a compilation problem on Solaris 9 caused by a missing
  definition of IPV6_V6ONLY.

o Setting --min-parallelism by itself no longer forces the maximum
  parallelism to the same value.

o [Zenmap] Fixed a crash that would happen in the profile editor when
  the script.db file doesn't exist.

o [Zenmap] It is now possible to compare scans having the same name or
  command line parameters.

o Fixed an error that could occur with ICMPv6 probes and -d4 debugging:
  "Unexpected probespec2ascii type encountered"

o Applied a workaround to make pcap captures work better on Solaris 10.

o Fixed a bug that could cause Nsock timers to fire too early.

o Changed the way timeout calculations are made in the IPv6 OS engine.

Nmap 5.61TEST5 [2012-03-09]

o Integrated all of your IPv4 OS fingerprint submissions since June
  2011 (about 1,900 of them).  Added about 256 new fingerprints (and
  deleted some bogus ones), bringing the new total to 3,572.
  Additions include Apple iOS 5.01, OpenBSD 4.9 and 5.0, FreeBSD 7.0
  through 9.0-PRERELEASE, and a ton of new WAPs, routers, and other
  devices. Many existing fingerprints were improved. For more details,
  see http://seclists.org/nmap-dev/2012/q1/431

o Integrated all of your service/version detection fingerprints
  submitted since November 2010--more than 2,500 of them!  Our
  signature count increased more than 10% to 7,423 covering 862
  protocols. Some amusing and bizarre new services are described at
  http://seclists.org/nmap-dev/2012/q1/359

o Integrated your latest IPv6 OS submissions and corrections. We're
  still low on IPv6 fingerprints, so please scan any IPv6 systems you
  own or administer and submit them to http://nmap.org/submit/.  Both
  new fingerprints (if Nmap doesn't find a good match) and corrections
  (if Nmap guesses wrong) are useful.

o IPv6 OS detection now includes a novelty detection system which
  avoids printing a match when an observed fingerprint is too
  different from fingerprints seen before. As the OS database is still
  small, this helps to avoid making (essentially) wild guesses when
  seeing a new operating system.

o Refactored the nsock library to add the nsock-engines system.

o [NSE] Added 43(!) NSE scripts, bringing the total up to 340.

o CPE (Common Platform Enumeration) OS classification is now supported
  for IPv6 OS detection.

[...]

Nmap 5.61TEST4 [2012-01-02] -> Nmap 5.61TEST1

[...]

Lots of Bugfixes!

Thanks to jschauma@ for analysing a NetBSD related problem,
and to David Fifield for providing the (upstream) patch.

1 files changed, 6 insertions, 7 deletions

diff --git a/net/nmap/distinfo b/net/nmap/distinfo
index 69b9946fed5..9fdd7de79db 100644
--- a/net/nmap/distinfo
+++ b/net/nmap/distinfo
@@ -1,9 +1,8 @@
-$NetBSD: distinfo,v 1.55 2012/03/08 11:43:47 wiz Exp $
+$NetBSD: distinfo,v 1.56 2012/09/16 20:29:06 pettai Exp $
 
-SHA1 (nmap-5.51.6.tar.bz2) = 572a08f043ee1ba7cfcb83f3c886daa7c7231fb4
-RMD160 (nmap-5.51.6.tar.bz2) = 3ececb8dd4fd4e747c4ca98198d2562143749570
-Size (nmap-5.51.6.tar.bz2) = 16876602 bytes
-SHA1 (patch-ab) = 5360e2aac721262e494dc98f3bd64572a74fb62c
+SHA1 (nmap-6.01.tar.bz2) = e397e453893930d14e9bb33a847d15b94b7ee83a
+RMD160 (nmap-6.01.tar.bz2) = 1b6f2b0e4f019d9cd069db14990364c45d463c7d
+Size (nmap-6.01.tar.bz2) = 21640157 bytes
+SHA1 (patch-ab) = 89a1794a1bf954ddf42d94d88de444efa52e5cfb
 SHA1 (patch-ac) = c22e8f6411b1152a6e7582c90e5ec5bd4c6acaad
-SHA1 (patch-al) = c56396c28d96314c8d7e8b19a92bd5db7959e289
-SHA1 (patch-nbase_configure) = 3db822d392defd92d531b71f466b61be82e525a1
+SHA1 (patch-an) = 33fb3aa23cf4beedcc9cb908b08d928cabab17c8