space long enough to make it fairly cheap. Cheaper than remaining on Earth and having to follow regulatory rules and taxes and other inconveniences.
So instead of going to countries with lax regulations (which probably won't exist anymore), they'll go to space where there aren't any rules at all.
The first ones to go will probably be failures, but some will succeed. Their success will drive others.
The exodus of resources and personnel, in combination with worsening local conditions, will prompt the failure of multiple states, perhaps even the majority.
Getting a job with an offworld corporation will become the goal of the majority, but most will be stuck here.
100 to 200 years from now, all current states will have failed, and the majority of easy-to-aquire resources will have been mined out, and Earth will largely be abandoned by these offworld corporations. What little resources remain will be insufficient to drive another space race, and whoever remains will forever remain. Or be conscripted for slave

labour. Which will probably actually be preferable to remaining on Earth, and therefore not be much of an ethical issue. Not that ethics will matter to any corporation who doesn't wish ethical concerns to matter. But I'm certain it will for some. Just as certain as it won't be for all.
Colonies will exist on Mars and Europa, multiple colonies per planetoid, under the control of multiple corporation/states. Probably as far out as Pluto there will be colonies and instalations.

This might not be a perfect representation of the future, but I'd bet everything I ever owned that if someone read this post in 2313, they'd be stunned at how close I was.

Now it's time for you to shit all over my thoughts or agree with them, in whole or in part.

 I think you are pretty close. There is little doubt in my mind that some corporation will set up a viable colony long before any government is capable and willing to. I also agree that most likely the first government set up will be very lax and since travel times will probably be rather long and communication with Earth will be slow at least initially they will probably be highly unregulated for a long time. It would be nice if wars could be avoided but you are probably right there as well, as soon as a colony becomes prosperous some government here on Earth will want to claim it. 

I think you are wrong about people remaining on Earth becoming slaves. The new colonies will be wealthy in resources like metals, but they will need a customer base and Earth's population will be a large customer base. Whatever resources we exhaust here, Earth will still be able to produce food on a massive scale that would be more difficult and more expensive to grow in the colonies. Things like meat would probably be extremely expensive luxury products and after a few generations Earth would probably be a tourist spot for people who were born in the colonies. Not to mention Earth would remain an intellectual center for a long time as new colonies would initially require pretty much everyone to work for survival and lack the surplus population to allow for things like scientific research. 

I'm using the terminology of slave labour in a slightly off-classic way. I don't think there'll be whips and chains or anything like that. But in a more modern, credit-style way, the terminology is arguably still applicable, if a bit leftist in tone. > >

I think food won't actually have all that much of an impact either way. I don't think it will turn out to be difficult to grow plants and livestock in artificial environments.
..And I won't be at all surprised if 3D printing or some variant ends up putting a grocery store in everyone's kitchen within 50 years.

It's possible that physical labour will cease to exist altogether in the foreseeable future, which would obviously have a significant impact on my OP.

i believe it's in one of the stories in i, robot that isaac asimov talks about an arid region of earth (earth by then is politically divided into several large regions) that produces all its food--traditional looking and tasting meat, vegetables, etc.--by synthesizing yeast.  this has completely taken the environmental factor out of the equation and obliterated starvation.