A friend of mine found out an interesting plugin for those admins out there that use ViM. It makes it easier for you (and your colleages) to see when you are editing a file that is managed by puppet:

http://blog.mricon.com/2012/04/puppet-eyes.html

This module will only work when your editor has root privileges, since the file it parses, state.yaml, is accessible only to root (for relatively evident reasons). When you try to modify a file that is currently managed by puppet, you will see a white on red warning telling you "This file is managed by Puppet":

This should let you know that your local changes will be overwritten on the next puppet run.

To install it, either just dowload the plugin/puppet-eyes.vim script and place it in your ~/.vim/plugin directory, or if you use vim-pathogen simply clone the entire repository under ~/.vim/bundle/.