GitX – Git GUI for Mac

From the website:

GitX is a git GUI made for Mac OS X. It currently features a history viewer much like gitk and a commit GUI like git gui. But then in silky smooth OS X style!

Features

• Detailed history viewer
• Nice commit GUI, allowing hunk- and line-wise staging
• Fast workflow
• Explore tree of any revision
• Nice Aqua interface
• Paste commits to gist.github.com
• QuickLook integration