I
f your father were dying of cancer, and you spent as much of your time going to visit him while he was still alive, how would you respond to someone who told you "Why are you bothering to go see him? He's going to die soon anyway."
This is roughly the way I am struck by claims that "nothing matters, because one day the universe will die". There is, implicit in this argument, the claim that nothing matters in itself, but only as means to some distant end. I'm a God-believer, and an afterlife-believer, but even putting those things aside, I think it is blazingly obvious that meaning is being generated all the time by the good things that are in the world. Reading a book is not good because it will bring about utopia, but for much more immediate, internal reasons. The same goes for raising children, taking pride in one's work, admiring natural beauty, and enjoying good food (I'm sure I could come up with some other ones too, given some time to think). Death and oblivion are certainly frightening concepts, but saying that "it was all for nothing" because things end represents a sort of nihilism about the value of existence itself. Species perpetuate themselves not to one day bring about the ubermensch, or the perfect life form, but simply to bring more life into the world to experience the goodness of being.
The ultimate fate of the universe is still a great cause for interest, and accepting a role in the greater works of the Lord heightens our natural purposes to a much higher plane -- but being overly concerned with the billion-year-future makes me think that one has lost sight of the present, and all that surrounds and sustains us.