Bazaar Explorer and Qbzr
Screenshot of the gannotate plugin. Notice color-coding of lines by age. When a line is selected with the mouse or arrow keys, details of the commit where it originated appear in the bottom pane.
Screenshot of the bzrk visualise plugin. This shows the various ancestries and how they intertwine, along with their commit logs.
Screenshot of the bzrk visualise plugin. This shows the diff viewer.
Command line interface
Screenshot of a new project being started in bzr (it's that easy).