git_nerd.vim is a NERDTree plugin to add visual indications of a file's git status to quickly see which files you have staged, unstaged and modified, or deleted in your project without any extra work.
At the moment git_nerd doesn't work with NERDTree, but the hooks for customizing tree nodes are in the works and should be coming out fairly soon.
Until then, if you'd like to help work on or test git_nerd, my fork of of NERDTree has some temporary hooks to work with.
Place git_nerd.vim in your ~\.vim\nerdtree_plugin\ directory along with replacing your NERD_tree.vim with the one from my fork and you'll be good to go.