What do you think will happen? I think space settlement seems pretty interesting, though I can't really decide on its likelihood. Space settlement, it seems to me, would also cause humanity to branch off into separate species, since the requirements for life in space are different than on Earth.
With growing population and technology, the future's pretty much open for anything, assuming we don't blow ourselves up too soon.
We're far too dumb as a racial feature to expand into space. Getting off the Earth requires resources so large that a corporation or government is required. Since corporations and governments are even more dysfunctional and sociopathic than individuals are, that means that there's essentially ZERO chance of forming societies off the planet.
We probably won't kill each other off on the Earth, but we probably will design an event that will kill most of Humanity, sometime in the future.
As for planetary-scale disasters like a Chicxulub strike, GRB or supervolcano ... within a few hundred years, Humanity should be advanced enough that pockets of Humanity would be able to survive any such single disaster. The vast majority of the Human race would die, of course, but as I predicted above, Humans will design such a near-extinction event for ourselves in the first place.
Eventually, squatting on the Earth, some interstellar event like a GRB will create one biosphere-killer too many and Humankind will go extinct. This will happen well before Sol expands into a Red Giant star and engulfs the Earth, which is about 5 billion years away. Human extinction will probably take place within the next several hundred million years.
Face facts, folks. Look at Human social development during our entire homo-whatever history. Even with suitably large brains, were too sociopathic and fearful and stupid to really form a space-faring civilization. Thinking man and raging man are united in each one of us, but those two never get along and often cancel the accomplishments of civilization. The next several centuries will be crucial as to whether Humans will persist -- albeit planetbound -- or go extinct. But expanding into space? No, Humanity is nowhere near smart enough to accomplish that.