Forum OpenACS Q&A: Response to Getting ready for beta - tagging and branching CVS
I would hate for a Free Software/Open Source project to end up using a non-free source control solution (Bitkeeper or Perforce). That would really suck. As in, REALLY suck.
Subversion I am pretty dang psyched about, though. There's also arch, which is pretty new and...interesting. I haven't played with it yet, but there's a Debian package, so I think I'm gonna. Located at: http://www.regexps.com/#arch
Supposedly handles atomic commits, yada, yada. Comparisions with subversion and CVS at http://www.regexps.com/src/src/arch/=FAQS/features.html
I'll be setting up arch to play around with soon...if it seems really interesting, I'll be sure to let everyone know.