How can you gaurantee that all the 'votes' from the community will be legitimate votes and that none of them will be 'bought' votes or just made up accounts from one ICO's pool of resources?
First of all, you will soon be able to see who upvotes what, so users will have full transparency on the upvotes. More importantly though, there is significance to the "reputation" a user has when it comes to promoting content, so 1000 upvotes from "new" users has less weight than 100 users whom have earned reputation on the platform. Not to mention, in-order to sign up you have to verify your email/device, making it a bit of a hassle for intruders to abuse.
I do agree thought that this is an issue with many other platforms like reddit, which is why I am focussing deeply on the integrity and transparency of the platform!