I'm excited to see more details on how R2 data is going to be replicated across different data centers in the future. I had assumed this was already operational based on previous blog posts so I'm a little disappointed to learn that is still TBD. It's a major reason I chose R2 over S3 as I don't want to manage moving around data for different tenants myself.
Strongly consistent replication is a harder problem. Working on it but it'll take a while. You can get replication today if you put a custom domain in front of your bucket and turn on cache.
With R2 you can also use a bucket or few buckets per tenant whereas with S3 that's not possible (even if you have a fat ENT contract with them from what I've heard). We've extended the S3 spec to make it possible to list more than 1000 buckets [1]. Currently we still ask that if you need more than 1k buckets that you open a customer support request for us to discuss your use-case.
