Bitcoin is unlikely to achieve a stable value in the foreseeable future, but that doesn't matter. Bitcoin is not destined to be used directly in ordinary commerce. Think about how HTTP is built on top of TCP/IP. In the same way, we will build new, stable currencies on top of bitcoin. They will be pegged to dollars, gold, oil, and anything else your heart desires.
I wrote a paper about this future, and if you come to the bitcoin conference in San Jose in May, you can hear me talk about it and ask questions at the "Bitcoin in the Future" panel.
The take-away is that buying bitcoins now is the best way to bet that these "child currencies" will be successful. They depend on bitcoin, and if they are successful, bitcoin values will go up.
how does your approach compare to Ripple?