It is currently recommended to use oacs-5-10. This is the version to be the next release. Don't try to use the HEAD version.
The move to CVS is on the agenda, but won't happen before the release of OpenACS 5.10. There is a version of OpenACS on github, which is synced on a daily basis. Most of the work missing for a final move to Git is a rewrite of the tagging/apm packaging code and guidelines, .... and some support to ease the handling a a few hundred git repositories that we have now.
