Is there anything easier than 'emerge world'? You have to really really dumb if you need something simpler than that.
Great surprise there!
Its easy to DOS the BTRFS and kill the system. A normal user can do it. Just create a couple of big files. Then, copy a large number of small files. You will get ENOSPC at around 90%. Then, delete the large files. Even with most of the space being free, it won't allow you to create new files. All new requests will get ENOSPC. Bug is at: https://bugzilla.kernel.org/show_bug.cgi?id=16508 BTRFS is a mess. Go read their mailing lists.
If you look at the photo closely, it says "Enhanced Write Performance" and "Encryption" as the new features. So, I would think that's an indicator of good things to come. The read speed and random IO speed was already very good with x25-m.