Maybe this is a misinformed question, but isn't the reason anyone is adopting it at all due to the fact they can later convert it back into actual currency?
But if you are business who takes money over the internet and is sick of the banking BS and you notice that there are a lot of people out there holding these strange coins which seem to have a rising value..
If you are a merchant then the easiest way to start holding it is to start accepting payments with it, which is easy enough to do especially if there are enough people holding it already.
At that point it has value not just because you can convert it , but because you can buy stuff with it.
The liquidity part of it is a big factor, but we've had pretty good liquidity for a while if you're willing to do a bank wire or trade with someone in person.
In other words it will hit an equilibrium value where the price modifiers in both directions balance each other, but nobody knows what that is.
Think it more like how the value of a futures contract might be determined.
Or final goods. Silk Road gives a final good endpoint for BTC