You also need to know that there’s the potential for a fairly major .gitignore bug on OS X: http://article.gmane.org/gmane.comp.version-control.git/2256...

Homebrew backed out 1.8.3 because of this.

I'm seeing a similar problem on Ubuntu with the packages installed from the git-core PPA.

Edit: Specifically, I've got ".* .un~" and ".*.sw?" in my global excludes file, but they're showing up as untracked (not ignored) when my repo's .gitignore has some !-type patterns. Perhaps something about the precedence of such rules was changed.

Hey Robin, indeed! I added a disclaimer about that in the article as well.