The 1.4 release of Bazaar includes handy improvements to the speed of log and status, new options for several commands, improved documentation, and better hooks, including initial code for server-side hooks. A number of bugs have been fixed, particularly in interoperability between different formats or different releases of Bazaar over there network. There’s been substantial internal work in both the repository and network code to enable new features and faster performance.

You can check out the full changelog at: https://launchpad.net/bzr/1.4/1.4/
And download it at the usual location: http://bazaar-vcs.org/Download