Since the abstraction is NFS for access, I wonder what the advantage over EFS is. Or more, why not just leverage this under EFS if it was a straight improvement. Compression and snapshots seem like some of the biggest wins over current EFS.
EFS performance is garbage compared to FSx for most things. They serve different purposes.
Compression and snapshots indeed are the largest improvements I see, as well as an order-of-magnitude higher performance. If your applications already rely on ZFS snapshots, filesystems, quotas, reservations, compression, etc. - this is a pretty huge release as it appears to enable a convenient multi-reader workflow without significant administration headaches.