Chris Mason was asked on the Btrfs mailing list about the state of btrfs-progs and whether a new release will be due out soon, since Linux distribution packagers prefer actual releases to just pulling in Git snapshots. For some perspective, the latest brrfs-progs release is v0.20-rc1 and it came one year ago.
Chris Mason, the Btrfs file-system maintainer, responded with, "The problem with the progs release is I keep finding more things I want to add. My local git tree has about a dozen commits that I feel are important enough for v1.0. I just have to cut it, the distros and others are completely correct in asking for an official release. In terms of the quality of the commits, I only put things into the master branch of the git tree that I have fully confidence in."
Aside from the mailing list thread author, who packages btrfs-progs for Arch Linux, other packagers and stakeholders have also called on Btrfs in the mailing list thread for the stabilization and releases of this Btrfs user-space code.
The btrfs-progs code and activity can be viewed via its Git repository.