Ultimately though it's pretty straightforward to write an accurate merge function for most distributed applications with the pro that you can think about them in a locally strong consistent manner. While I could see a better ORM style auto-merge system existing I don't see the hassle of CRDTs being worthwhile when the vast majority of geo-replicated systems have extremely small numbers of record level write conflicts across Geo's.
I'd venture that the number of potential write conflicts introduced by FB users hopping geo's is small enough to simply report an error to the client and forcing a retry - or handled by a hand-shake before the customer crosses GEOs
Is there any practical database application where a CRDT is useful?