Pretty cool, but you could add a brief comparision with vim-gitgutter to the Readme, or explain why you felt the need for a new plugin.
Yes, I knew about vim-gitgutter before, I even contributed to it. But in the end I just didn't like the codebase and started my own plugin. And because I like programming VimL.
The main difference is probably the support for other DVCS. Moreover, execution speed and high configurability are two of the design goals.
Rest well. :)