A currency which changes in value by around 40% in a 24 hour period is completely useless for the transactions I mostly deal with. We worry about a few percent change over weeks and insist on hedges.
Imagine saying to someone - I'll put 1000 BTC into your venture when you reach the next milestone in two months. What's that going to be? USD 100,000? USD 50,000? USD 1.50?