Very useful, thanks. I just bought a new mac and it defaults to zsh, so figured I might as well as make the leap from Bash to Zsh.
Only comment I'd make is you need to include:
setopt prompt_subst
else the $vcs_info_msg_0_ won't get expanded in the prompt. With your help and a little more searching I ended up with:
autoload -Uz vcs_info
setopt prompt_subst
precmd () { vcs_info }
zstyle ':vcs_info:*' check-for-changes true
zstyle ':vcs_info:*' unstagedstr '%F{red}*%f'
zstyle ':vcs_info:*' stagedstr '%F{green}*%f'
zstyle ':vcs_info:*' formats ' (%F{blue}%b%u%c%f)'
PS1='[ %B%n%b@%B%m%b:%F{green}%/%f$vcs_info_msg_0_ ] $ '