One alos has to consider though that bitcoin is much more valuable than gold for the fact that it's digital, and therefore has a lot of benefits. It can not physically be stolen (although you should take measures against hacking), and it can easily be transfered across the world in milliseconds, something that's impossible with gold. And it probably has many other features that gold can never dream to have..
Also, if physical gold were widely used as a currency, instead of dollar bills or whatever, I imagine demand for it would be higher and its value would increase. If Bitcoin succeeds, demand for it may become higher than demand for gold is now, so that's another reason 1 BTC may be worth more than 10 kg of gold is worth now.
