o Added regular expression support for the format search, match andsubstitute modifiers in tmux(1).
o Added a -v flag to source-file in tmux(1) to show the commands and line numbers.
o Added simple menus usable with mouse or keyboard in tmux(1).
o Introduced the command "display-menu" to show a menu bound to the mouse on status line by default, and added menus in tree, client and buffer modes.
o Changed the behavior of swap-window -d in tmux(1) to match swap-pane.
o Allow panes to be empty in tmux(1), and enabling output to be piped to them with split-window or display-message -I.
o Adjusted tmux(1) to automatically scroll when dragging to create a selection with the mouse when the cursor reaches the top or bottom line.
o Fixed a tmux(1) crash when killing the current window, and other bugfixes.
Would love to see a demo of these cool now tmux features. (sorry, I don't really know how to format that email text for HN)