You may have read that a lot of prominent people have recently moved to Git and are loving it. I too am one of those who fancy this new kid on the block but never got very far with the bundle I started for it.
Fortunately Tim Harper recently picked up on my initial efforts and has done a great job at not only making this bundle functional but also downright impressive :)
For those too lazy to click the link above, here are the short install instructions:
mkdir -p /Library/Application\ Support/TextMate/Bundles cd !$ git clone git://gitorious.org/git-tmbundle/mainline.git Git.tmbundle osascript -e 'tell app "TextMate" to reload bundles'
After having installed it you can press ⌃⌘T in TextMate and enter
git to find the “Administration → Update Git Bundle” action. Use this to update the bundle (it will automatically reload after having performed the update).