Seems no different than if the buyer had sold her Bitcoin and paid Virgin Galactic in cash. The real trick will be when they can accept Bitcoin, keep the Bitcoin, and make any refunds and adjustments in Bitcoin.
I don't see any other way to bootstrap a new currency.
I'm not sure if this differs for six-figure transactions, but transacting fiat currency generally costs a vendor ~3%.
Receiving bitcoins and immediately converting them back to USD/GBP can be done for less than one percent of the amount of the transaction.
1. Bitcoin is no less a fiat currency than the U.S. dollar or Japanese yen.
2. For small retail transactions, yes, 3% seems right. Larger transactions, however, are generally done by wire. These transfers carry a fixed fee and are generally a very small percentage of the transaction value.
Depends on what you mean by "fiat currency", which tends to get used with a few different (if related) meanings. One is "non-backed state-issued currency". Under that definition it isn't. Another is "currency with no intrinsic value". Under that definition it is.