I've recently released a buildout extension to checkout packages in a buildout from various vcs.
Here is a buildout config used to install this blog's skin package. This checkout deliverance from svn and pyquery from his bitbucket repository:
[buildout]
newest=false
parts = eggs
index=http://pypi.zopyx.com/
develop=
.
extensions=gp.vcsdevelop
vcs-extend-develop=
svn+http://codespeak.net/svn/z3/deliverance/trunk#egg=deliverance
hg+ssh://bb/olauzanne/pyquery/@tip#egg=pyquery
[eggs]
recipe=zc.recipe.egg
eggs=
GawelOrgSkin
This extension is less than 100 lines of code. All checkout stuff is handle by pip which support many vcs.