Reposted from Reddit...
Steemit is immune from the same kind of attack (at least cheaply) but instead allows stakeholders to determine the agenda. Arguably it has swapped one flaw for another potential flaw, but at least there are some checks and balances to provide accountability. All votes are public and auditable, and stakeholders who cheat have something to lose. It relies on the stakeholder majority being honest and policing any bad behaviour with the reputation system. SteemIt may have further improvements down the line to improve accountability.