Players will support both, but what about HW acceleration that will come eventually? That's my concern - for future proofing with mobile devices you should use AV1.1, correct?
The other things I see are a new option that doesn't break existing AV1 streams, and a couple changes that look like essentially editorial cleanups that were deferred during the spec freeze to avoid confusion.
They were right not to do these changes during spec freeze, but (at least from what I can see) they're not practical issues for folks considering AV1 encoding today.