This is the latest release of Ardour. It is not publicized on the main ardour page but it is posted within the releases directory. The package itself is stable. This is a new submission
Created attachment 44971 [details] ebuild for ardour-0.9beta21
See my comment on bug 70356: beta21 has show-stoppers with jack sync. You can locally bump the ebuild, but beta21 will not go in the tree.