I was very lucky to purchase some bitcoins today. I think you are spot on. If less than 50 million will be made, the value per bit coin will be ridiculous in the coming months...
There is only ever going to be 21,000,000 Bitcoins in circulation. Of course the price of 1 Bitcoin is going to be through the roof.
BTC can be replaced at any time. The infrastructure is compatible with any other alt.