There seems to be a successful divide/conquer tactic going on between goldbugs and bitcoinbugs, judging by the typical attitude towards BTC at zerohedge. So perhaps focussing on similarities between the 2 could be useful - no banks involved, decentralised creation, not created as debt, no usury are a few that spring to mind. Security issues could be worth discussing, too - would you keep your gold at the comex (mtgox), or a safe (cold storage wallet)? I see gold and BTC as complementary, gold for long term holdings, BTC for spending or to profit (perhaps) from volatility, if that's your bag.