Coinbase Custody is exploring a range of new assets: And Steem is one of them!!!
https://blog.coinbase.com/coinbase-custody-is-exploring-a-range-of-new-assets-e700496844be
Coinbase Custody is a custodial service for institutional clients optimized for storing large amounts of cryptocurrency in a highly secure way.
This could be big news for Steem
Any coin or token I have seen added to coinbase always gets a lot more attention from investors.
They blog post does state though, that this would be just for storage and not trading on Coinbase, but that's a great first step in my opinion.
I'm Jeff, and I'm 
I'm a top 20 witness, along with my project partner 