To celebrate the 10th anniversary of this powerful tool, Nmap 4.50 has been released. It is the first stable release in more than a year and the first major release since 4.00 two years ago.
The changelog shows 320 changes since 4.00. It has a brand new GUI and results viewer (Zenmap), a scripting engine allowing you to write your own scripts for high-performance network discovery (or use one of the 40 scripts shipped with it), the 2nd generation OS detection system (now with more than a thousand fingerprints), nearly 1,500 more version detection signatures and a lot more.
For more information, browse to Fyodor’s homepage.