I've just completed the rename of the 'ng' branch to become the new 'master' branch. The old 'master' branch is now called 'alpha'.
If you have an existing checkout (clone) of the Rakudo repository, it's probably a good idea to get a new fresh clone rather than trying to pull updates from the existing repo. We know that the new 'master' still doesn't pass a lot of tests but we expect that to change soon. People who want to continue using the older-and-more-complete Rakudo should either use the new 'alpha' branch or the 2010-01 ("Minneapolis") release. Thanks! Pm