OpenSuSE uses btrfs by default and relies on it for one of it's killer features. Before a system change, such as installing updates, changing services configuration, etc, is made using YaST, snapper takes a snapshot of the root filesystem. If something breaks, just roll back to the previous working state.
I'd say that for the OpenSuSE folks, btrfs falls squarely into the "good enough" category.
I'm a big opensuse fan, but none of my opensuse machines are running btrfs.. Although, besides the stability (which can't really be much worse than ext4/xfs which is what I apparently choose on the two machines) I think what drove me nuts about opensuse's use of btrfs was all the subvolumes. Which are cool, but just another thing for me to deal with, and my computing theory for the past few years can be summarized by "KISS, unless its really hurting".
I'd say that for the OpenSuSE folks, btrfs falls squarely into the "good enough" category.