Yes, Falcon 9 v1.1 and Falcon Heavy have not yer launched. We will know their costs when they are reliably working and have been operating at market price for some years, all first launches have already been booked at special prices for early adopters.

Fair enough, but SpaceX has already booking launches guaranteed at their quoted prices, so there's nothing hypothetical about them. Whether they can deliver reliably without going bust is perhaps more of an open question, which is fair enough, but they've certainly put their balance sheet and reputation where their mouth is.

You are correct that, slightly re-stated, there's nothing hypothetical about the amount of money you have to give SpaceX to put your payload on a Falcon that you reserve today. But you missed his point.

We don't know what the failure rate of the Falcon will be, whereas we do know what the failure rate of a Proton is (~10%). Satellites are expensive and delivery is not guaranteed, so every launch provider always gives a discount to early customers who put their payload on one of the first few launches of a new system.

Pvarangot's point was that the price for booking a launch today is almost certainly less than, say, booking a launch after Falcon has had ten successful launches on its first ten attempts. If Falcon has Delta's failure rate, then SpaceX can charge a premium. If Falcon's failure rate is closer to Proton, they will have to underbid the Russians to get customers. We won't know until Falcon has a few launches under its belt. Saying they are booking launches at guaranteed prices today is true, but only gives a hint to what it will cost customers five years from now.