I see a lot of people flocking to the idea that the supply will double overnight. In reality the extraction of all this gold will take a very long time and is also an expensive undertaking. Those in power with vested interests will also make sure that the supply ratio is monitored so as to not hamper gold's price all too much.
As for the store of value debate, not every single ounce of gold is intended for cold storage. The metal itself will still find its way into luxury items and heavy industry.
Don't get me wrong, I'm all for Bitcoin and take this news as positive for BTC, but one also needs to consider the actual processes in play over longer time frames and not jump to a bandwagon conclusion.