Whether our species will survive that long remains to be seen. Natural gas will soon be depleted. The damage our species has done to the Earth is significant. Millions of species become extinct every year. Overpopulation. Poverty. We now have the weapons to destroy a significant part of humanity with just a few blasts, and the resulting radiation will kill off the rest.
We are at a crossroads right now. Either we clean up our act and advance technologically enough to go out of Earth and eventually out of our solar system, or we die.
I agree, I think the key idea here is that we have to change.

Not use some temporary fix.
Well if we don't change, even finding another planet is only a temporary fix. We'll just trash that planet too... and I'm sure people will still want to keep their weapons.

And even overpopulation/poverty, sometimes I feel like people use this idea as a scapegoat, as an excuse to not do anything. Some people even suggested killing off people to solve the issue. Seriously?! "Overpopulation is destroying the planet." No, actually
we are. Even if we got rid of all the people in developing countries who are supposedly "overcrowding our planet and causing poverty", we would still probably complain about not having enough resources. Doesn't 20% of the world use 80% of the world's resources? I guess you could call me an environmentalist, but I'm kind of skeptical about how the whole overpopulation thing is being presented.
Oh and I also don't understand why some people are so against the idea of global warming...
They think "global warming's not real, all this environmental stuff is stupid. We'll be fine."
Even if it's not entirely anthropogenic does not mean we're doing a good job taking care of the planet. There's pollution, resources running out, a hole in the ozone layer, species dying like you mentioned... etc. The message is still important, we've got a responsibility here to clean up the mess we've made.
Ok so I went off topic, but this is what's on my mind. And I felt like speaking my mind

Anyway, it's not too late to fix things.
Back on topic: I really don't care when the world is going to end, but it'd be kind of sad if we just destroyed ourselves like that.
But even beyond this, even if we survive, some people are thinking of the singularity, merging people with robots, or even getting rid the physical body completely, turning people into nothing but information.
Ok now that's just creepy.
