$ brew install vim

so I need a custom brew formula:

$ brew install https://raw.github.com/Homebrew/homebrew-dupes/master/vim.rb
$ which vim
/usr/bin/vim

My solution to using the correct vim, was to prepend /usr/local/bin to $PATH instead of having it somewhere in the middle. Now my $PATH looks like this in my .zshrc:

export PATH=/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/X11/bin:/opt/local/bin:/usr/local/git/bin

and, as evidence:

$ which vim
/usr/local/bin/vim
$ vim --version | grep +ruby | echo $?
0
$ vim --version | grep +python | echo $?
0

Allright, we're good to go!