[Gold] is the basis of exchange for most national currencies[..]
Out of curiosity, besides the Swiss Franc, can you name 2 national currencies that continue to use a precious metal standard? Afaik, most countries explicitly moved away from such things because they like the ability to devalue their own currency if needed. This doesn't diminish the validity of your point though.
Aah, but you're looking at it from the wrong angle. It is exceptionally rare for the value of finite resources such as gold/silver to change. What's actually happening is a fluctuation in the market and economy - just because the price of gold goes from 100$ per troy pound to 500$ per troy pound (purely speculative numbers) doesn't mean that gold's value has increased - it means the value of the dollar has decreased...
Comparing the value of gold to the consumer price index seems like a reasonable metric, however. It will approximate how much goods you could buy with some weight of gold, assuming a perfect trade (and the cpi calculation didn't change year to year, which it sometimes does). That illustrates that there have been some fairly large changes in gold price over the last couple decades.
I think the value of btc is that it isn't dependent on a government and while conversion to and from it can be regulated, btc exchange generally cannot be, without controlling an extremely large portion of the compute network (or making use of BTC as a currency illegal, or simply taxing the ever-loving crap out of block generation). No, btc trade is not anonymous, but how often do you deal in cash or barter recently? They're the only exchanges that do offer "complete" anonymity, and they're just not convenient. (Note, things like zerocoin do offer perfect transaction anonymity, if adopted, but I'm not sure that's a desirable feature.)
The key problem with btc is exchanging it for goods and services. There is a minimum latency on the order of an hour to prevent double-spend and that's just not reasonable in a world where you want instantaneous trust exchanges for money and immediate gratification for goods. That pretty much blows adoption out of the water for physical exchange (imagine waiting for even the 1st comfirm in line at McDonalds or the gas station) unless something massive changes with bitcoin's organization and trust model. I trust the security problems with the wallet can be resolved, though history shows long term trust in crypto models usually stabs you in the back.