I'm bullish on China's potential to be a reserve currency within 5-7 years. They are making many moves to cultivate foreign nations with yuan exposure, and their first move may just be to surpass the euro in the reserve currency game. A gold backed currency in an age of devaluing currencies does sound nuts, but if it were to boost their nation's purchasing power on the global market, it will mitigate oil and food import costs. Oil is incredibly important for them as they import more than the US does. If they do not want to be the reserve currency, they definitely want to be a reserve currency, as do other countries. This is about knocking the US down a peg or two, and in the Sun-Tzu fashion, a way to fight without firing a shot. Their in, as would be Russia's and Brazil's, would be reconfiguring the international financial system focused on dollar reserves to an altered system based on IMF special drawing rights.
IMF SDRs are best broken down on Wikipedia in simple terms. SDRs are claims to reserves by members countries. The members with stronger positions can exchange them for claims on the weaker members. The key thing that China, Russia or even Brazil could make a play on is that the SDR can only be exchanged for four specific currencies: Japanese yen, British sterling, euros and US dollars. After a dollar crisis and another shock to the dollar denominated financial system, the fear of relying on the dollar may allow for alternatives. China-Russia could push for a gold or even bimetallic system, but they could also make a push for SDRs to rise to a new role and allow for nations to have a go between not so dollar dependent. The key is what makes up the SDR exchange. Check out the list of economies by GDP. If we drew up an SDR bucket, including the Chinese, Russians, Brazilians and even Indians would make sense now. If the euro holds, and I don't think it will, the euro can gladly be in the SDR bucket, but even then, it's share of the SDR could be pared back. A disintegration of the euro could leave the German Mark as the only euro remnant in the SDR bucket. A second dollar fiasco would give credibility to the idea of other currencies being in the SDR bucket as well as the SDR itself changing roles.
The shaking up of the SDR make up as well as changing how it is used will most likely come with another push: changing how the IMF leadership is selected and who is serving on its board. The Chinese, Russians and Brazilians are not going to push for all of these changes to see Americans-Euros still at the helm. Asian countries are still angry about the draconian measures that the IMF forced on them after the '90s Asian currency crisis. South American countries share similar memories. Changing an institution like the IMF to allow for non-Western control affects foreign intervention, bailouts, trade and other geopolitical tensions. If China is playing a long game for hyperpower status, or even just regional hegemon in the Pacific, removing the IMF tool or placing the IMF tool in its hands is a rather important gambit to attempt in a time of crisis. It is easy to doubt this or even question the SDR being twisted to this purpose or a purpose that benefits China, but the IMF, World Bank and SDRs were all born out of a crisis and new global leadership. Nothing is permanent. Current institutions will be altered to fit the new order or entirely new institutions will be built.