Steem's only as decentralized as its stake distribution.
I guess Justin controlling around 20% of the entire pool isn't THAT centralized, but it would be something of a challenge to co-ordinate sufficient SP to block him if all of his steem-intentions turn out to be bat-shit crazy, especially as he's probably going to have a few fairly wealthy supporters come to the site on top of his 10s of million of SP.
It's a tough sell.
Probably best to just carry on as usual, without promoting Steem, until we know more.
I am powering down mind you, just a couple of week's worth.
promoting steem worked well for me as I need to be active where people and traffic actually are, and that's not on steem. It kinda keeps me in the loop while I don't have as much time to post as I use to.
Fun times ahead, I need to go update my witness votes, I think I have a few free. time to make sure I use them (not like my SP will make any difference if Justin uses his)