I think OP was asking in a "what if" scenario .... even though he will not be there when it happens...
The price will most probably increase, if there are still people using it and mining it, but at the rate technology improve, we predict that Bitcoin would not be in use, because it would be replaced with a much better technology.
So in theory... 21 million Bitcoins can be mined, but I would bet against that ever happening.
There'll be some nostalgic computer scientist who mines the final dust from the original blockchain on their toilet or fingernail computer.
Once enough money is poured in, 'good enough' is a powerful incentive to keep things as they are. It's not a myspace/facebook where you can skip to the new technology with a couple of clicks and lose nothing.
Perhaps bitcoin will slowly morph as the years go by with the original token on the chain being fully transferable to a fresher incarnation.