[gonewest]

We're serving git over https using apache2, where apache handles authentication via LDAP. We also serve subversion repos with a similar setup. We use separate web services for search, code review, CI, and issue tracking.

Running this way does involve more moving parts, but every part is relatively self-contained and we can replace one thing without disrupting everything.

[Edit] one other benefit I should add, all the other services like code review and CI are compatible with git and svn, so the development teams have consistent tools regardless which vcs they're running for a particular project.