Not enough people hold physical to justify the govt effort. Gold will only get taken if the USD goes to zero, otherwise its just QE 4, 5, 6, 7, 8 and 9, kick the can until the entire show falls on its arse.
IMF will issue the SDR globally if they have to bail out reserve banks. Perhaps then we move back to a gold backed currency. I suspect just like every other time after a huge crash there will be a big war and QE will be the least of our worries.