There is no real commerce in bitcoin, including SilkRoad. Exchanging USD for BTC for USD only stabilizes BTC, not adds value. It does add value to the USD economy and profits to MtGox and the vendors selling their wares.

Probably 90%+ of bitcoins are being hoarded and not put to use. "Invest" a million USD into bitcoins and you get 13 cents of fiat paper value back, or a loss of 99.99%. The rest goes to the ballerz aka speculators aka the freeloaders.

Now SilkRoad COULD be gigantic to bitcoin, if the vendors complete the economic cycle and dont cash out or hoard. This possibility is what gives bitcoin hope, as a backup to the gov currencies. If the gov currencies stop working out, you can bet theres going to be a lot more interest in bitcoin.

But again, while the gov charade continues, no one cares...you are right. But when the credit card stops, which it will, and reality hits, hopefully something like bitcoin will be around to ease the suffering. Until the time of the NEW US dollar/gov currency...and then we play the game again...heck, the new USD could be a digital currency!