I think you raise a good point about Steem including an economy. I would also add that it will potentially be a very fair economy compared to the marketplaces of google and facebook, which only aim to maximize the income of their owners. These facts combined with many other positive aspects of Steem make the potential market cap of Steem higher than any of the incumbents.
Steem might be the first flash billion dollar blockchain. The beauty of their platform is that it can scale right now, with a lot of leverage, in a whole host of directions. It will be important for community members to step up and make sure a positive financial structure forms. Have you seen any more news about Ethereum integration?
No, I haven't. If I guess right, what you are referring to is Dan's article about anyone being allowed to build upon Steem. He was just pointing out that Ethereum-type contracts are very possible on Steem, but I haven't heard of anyone actually planning to do it.