As the CBOE bitcoin futures product goes live there are lingering questions with the exchange where they will base their pricing; Gemini is run by the Winklevoss twins but has had a number of issues including low volumes and system outages; Gemeni is currently ranked 14th according to CoinMarketCap; while well connected because of the Winklevoss twins critics worry they can be potential targets for price manipulation; as the futures market goes live there will be a lot of interest to see how this plays outs. Source.