-Will we colonise the solar system? When?
We'll colonize the solar system soon enough; although I doubt most of them will fit the expectation of a colony. They'll be more like the Antartic research stations, with the exception of the Moon, which would be a big research station
-Will we ever travel beyond this solar system? When? How? How far?
Anytime soon? Doubt it, very much. Maybe in the next millenium. How? Maybe our grandsons and granddaughters will hear about it when they turn 75. How far? If we find a viable way, as far as we can.
-How long will humanity survive? Will we evolve into something else, be wiped out by war/ catastrophe or have we reached the point where we can overcome or avoid anything nature can throw at us?
Despite the news we hear, I think a good portion of the world is level-minded for us to be wiped out by war. If we do get wiped out, it will be because of disparities in living standards. As for that second part, I think nature will find new ways to challenge humanity; if not on earth, in space.
-Will civilisation continue on its path or are we headed for a catastrophe and a new dark age?
Civilisation will continue on, as it had for many years before.
-Will we meet intelligent ETs? Will they come here or will we have to go to them? How will we get on with them?
Only a matter of time. How will we get along with them? That won't be up to us.
-Will we achieve AI? When? What will be the ramifications for humanity? Will we all become cyborgs?
We'll achieve AI a lot sooner than we can achieve FTL engines, that's for sure. I don't know about the details, but if we do create AI, We'll have new truckloads of social problems that will have to be solved over time. Now, about being cyborgs, that's really up to a person's choice. People who are blind, deaf, mute, crippled, or mentally disabled won't mind cybernetic implants and parts which will make them normal or 90% normal again, but normal people will abhor the idea of having a limb cut off and having it replaced with a machine.
-What about genetics? Will future generations of humans be improved (or maybe "improved") by gene-tweaking? Will people accept this?
Gene therapy could go two ways IMHO - On one side, it could become like abortions, and on the other, it could become like pLastic surgery. It really depends on the cases in the near future.
-What about neural technology? Will our great-grandchildren have computers embedded in their brains and direct mental access to everyone else?
I don't see any conventional pros in neural technology. I'm against it, except for medical purposes. The potential for damage is to big IMHO; a neural virus could put people into comas, seizures, and even brain death, in a matter of seconds, and it could spread faster than the internet, since you'd only need to think in order to transmit.
-Will communications technology fundamentally change society? Will government become obselete when we're all jacked into some gigantic global network? Will we become the Borg?
The internet has already changed the world in ways unforeseen, and it keeps changing how the world thinks. What makes you think it will stop changing? Although Governments will exists as long as civilization exists, even if total democracy is achieved. Why? 2 reasons: People will be too busy to vote on every resolutions and bills, or people just won't care.
-Will the usa conquer the entire world? How long before the new empire crumbles?
The USA will never conquer the entire world: it doesn't want to, and if it does, the rest of the world won't want to speak "American".
-What art/ literature/ individuals from today will be remembered for centuries to come?
Important media icons, such as Lord of the Rings, Titanic, Pokemon, and Harry Potter.
-Will humanity ever be united and war made a thing of the past, or is our tribalistic instinct too strong?
Wars between countries, where it kills millions and millions of people in matters of minutes? Yes, I think that we will be eventually be horrified by the idea that we will all be killed by a button, and work together to build peace. But wars as in domestic issues? No. There will never be a state where everything is solved and everything is known and everything is perfect.
-Is national identity something that will come to an end or will expansion to other planets create more nations and more conflicts?
No. Never. As long as history exists, National Identity will never go away. But the ugly parts of national identities will fade away, as long as people respect each other. And of course more national identities will spring up soon enough. To say that it won't and we will all see ourselves only human is ridiculous, IMHO, and unrealistic. I will most certainly see myself as something else after I grow up under a green sun, see Carbon Dioxide Ice caps, and breath that thick oxygen/nitrogen/argon atmosphere.
-What is the future of religion? Can it stand up to the advance of science? Will it evolve, die out or will it stay as it is?
It'll most certainly evolve; maybe perhaps we'll worship unified field theories as god itself, just as the greeks did once, with their pythagorean theorems.
There goes my two cents...