Three-tiered VM development setup with support for branch switching

[Burke Cates <burke.cates@gmail.com>]

I read Joe Maller's blog post "A web-focused Git workflow" (
http://joemaller.com/2008/11/25/a-web-focused-git-workflow/ ) and
thought this would be a great replacement for our current
scm/development workflow at my job, which I won't get into here. My
main concern with switching to a three-tiered setup using Git is that
switching branches on a workstation and pushing to the "hub" repo
would result in no change in the "prime" repo when "hub"'s post-update
hook runs, as it will not switch branches.
The only solution I can think of involves ripping the branch out of
the refspec that is passed to the hook and using that to call checkout
and pull (or possibly a checkout -b --track newbranch if I dont have
the branch locally on prime). I feel like this is a pretty nasty hack,
but I might be missing something completely that would make this sort
of setup much easier to pull off.
What I'm trying to pull off here is this: devs can code at their
workstations with whatever tools they want, and push changes to the
VM's with git. Hooks will be used to initiate makes for testing and
for pushing changes to other nodes in the test-cluster (who will have
the same make hook). The only obstacle at this point is the branch
switching.