Somewhat compacted version of this patch set (i.e. fixes of nasty issues rather than less significant stuff) has actually made it into 3.17-rc1.
Just looking into GIT commits log:
And speaking of butter replacing ext4... in fact I use btrfs on some non-critical systems and it "just works" for simple cases. Yet it provides nice things like snapshots and recent versions got fairly good performance as well, at least in more or less common use cases.
Merge: 53b95d6 8d875f9
Author: Linus Torvalds <firstname.lastname@example.org>
Date: Sat Aug 16 09:06:55 2014 -0600
Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
"These are all fixes I'd like to get out to a broader audience.
The biggest of the bunch is Mark's quota fix, which is also in the
SUSE kernel, and makes our subvolume quotas dramatically more
I've been running xfstests with these against your current git
overnight, but I'm queueing up longer tests as well"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: disable strict file flushes for renames and truncates
Btrfs: fix csum tree corruption, duplicate and outdated checksums
Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch
Btrfs: fix compressed write corruption on enospc
btrfs: correctly handle return from ulist_add
btrfs: qgroup: account shared subtrees during snapshot delete
Btrfs: read lock extent buffer while walking backrefs
Btrfs: __btrfs_mod_ref should always use no_quota
btrfs: adjust statfs calculations according to raid profiles