We have to wait,listen for further information on the exchange of Bitcoin gold on the Internet, the furum on the way foward
BitcoinGold is already being traded on several exchange sites including HiBtc and Bittrex all you need is to visit their offical site to see this list of several others.
On the acceptance of BTG for ICOs I think its really still early to decide that because quite an amount of ICOs are already running before the fork and new ones will have to study the coin before considering its acceptance couple with that fact that this coin is only a day old or less.