Before a milion $ company can use bitcoin, as explained some posts ago by nmat, they must be widely used by smaller ones to avoid big prices fluctuaction.
This is just wishfull thinking.
Obviously: no one can tell when, if, and how many would adopt bitcoin in future. But IMO the path should pass from little-mid companies.
The clasic counter-example is the failed "web currency" beenz, which was used almost exclusively by huge companies.
beenz was totally different from bitcoin: centralized and more similar to fidelity point in his structure than to a true monetary system.
Stability is one thing. The other is fraud-resistance. The big businesses actually have money and skill to audit the source code.
You can scam a small businessman into believing that the bitcoin doesn't allow chargeback. Big businessman will hire somebody to read the code and will ask pointed questions like: what is this code doing erasing transactions and removing money from my wallet?
I don't get the point
Bitcoin is secure enough for transactions. Online transactions and big money movements can be approved with a sufficent number of confirmation to make them absolutely non-fraudable. The code is open sourced so is readable by everyone.
Why do you think that there is a fraud risk?
Big businessman also knows that a self-deluded enthusiast is completely indistinguishable from a persuasive and skilled scammer.
Again don't get the point