I've been a ZSH user for about a year now and I've been enjoying it a bunch. I'm also an emacs user and I've learned to love being able to use Emacs-style word jumping commands in apps that use GNU Readline.
@daguar was going on about how great iTerm2 was recently and I figured I should give it a shot. A few minutes later I was getting these inexplicable [C and [D messages when I went to bop around my command line like I'm used to.
A few websites give recommendations on how to work around this or what you're doing wrong, but none of them had an updated fix. Here 'ya go. Put the following code at the bottom of your .zshrc and enjoy the bliss of Emacs keybindings everywhere you're used to.