It probably will head towards subbreddits in terms of design which would leave a gap in the market for a more social site which minds seems to be. I think being an early adopter for a SMT could be great for it as they would probably get a lot of users from Steemit who are more interested in that type of social media but who are involved with the STEEM blockchain already.
It would make perfect sense to me to use minds as my front site and just share any good blogs that I create on Steemit which would increase my exposure across both really. It would be an interesting experiment if nothing else as their site is already tokenised really so they would have any easy way to monetize them with STEEM.