I agree with Vitalik on this and think its a horrible idea to use coinvoting for content curation. His point about public vs private enterprises is very interesting. Put another way, private corporations and DAOs modeled after them, where tokens represent shares, are suitable for coinvoiting. Governance of public goods, or commons is not. Any sort of coin or point-based reputation mechanism will be very easy to game or will devolve into plutocracy. Pagerank is much better suited for reputation and makes it easier to construct a more secure system.
Coins are great in prediction markets though, at least as long as predictions are decoupled from outcome. As we know predictions markets can also generate useful information. This information can be a useful signal, but again the whole point of a prediction is that it doesn't dictate outcome.
Interestingly, Vitalik has suggested a content prediction market similar to Relevant here: [https://ethresear.ch/t/prediction-markets-for-content-curation-daos/1312](https://ethresear.ch/t/prediction-markets-for-content-curation-daos/1312) . In the case of Relevant the Reputation system of each community serves as the DAO that decides the outcome in Vitalik's design.