When installing Fedora via the Anaconda graphical installer there is extensive support for creating lvm2 volumes groups and logical volumes. But there is no support for doing any similar operations with btrfs. btrfs is treated as purely a filesystem type and nothing more. btrfs of course supports subvolumes, snapshots, multiple physical volumes arranged in a RAID configuration and many other useful things. But there is no way to make use of these things when doing an install via Anaconda. This is particularly vexing to me as I've been wanting to upgrade into a snapshot of my original root subvolume. Also, I've been wanting to mount a particular subvolume as the root filesystem without having to set a 'default subvolume' in btrfs. This is a feature request. But I think that this is a more important feature for the 'default btrfs filesystem' goal than even fsck is.
*** This bug has been marked as a duplicate of bug 689517 ***