This fork adds a couple of files (textile.snippets, mail.snippets, and markdown), but the main addition here is the modification of tex.snippets. I've swapped auto folds (with (fold) and (end)) with manual folds ({{{, }}}), added new environments, and added snippets for things like citations, footnotes, and emphasis. All my new additions are at the end of tex.snippets if you are interested.
Quickly install with:
git clone git://github.com/msanders/snipmate.vim.git
cd snipmate.vim
cp -R * ~/.vim