Sadly the article never describes HOW they transfer the data. Simply sending 3PB on the wire will cost a fortune. Maybe Google does have some non-public service like AWS Snowball?
Nothing against the author, but it sounds like another story that Google PR pitched and influenced. It is normal these days. I am sure AWS does the same. That is why the technical details may be light. The submitter is likely a Social Media Manager for Google (nothing wrong with that - kudos for not obscuring it!) I, too, have wondered about the technical details when I see stories like this. If the data was original…
Unfortunately, a technical deep dive on the exact parameters of the transition wasn't really in scope for this piece. I tried to include detail where I could, and Evernote has a really wonderful 5-part blog series that goes into many of the details of the transition. (It's now linked in this post.)
To provide some additional details on the transfer: Evernote was going from data centers in California that it owned and operated to Google, not from S3. Technically speaking, the migration isn't 100% complete, as Evernote is still finishing the transfer of its attachment files to Google.
Evernote did not disclose the exact details of how that transfer was executed on the record, and thus it did not end up in my piece. Thanks for reading!