@ DeadO: Yes, there's something to be said for cutting the apron strings and heading out to greener pastures. But I suggest that the economic security of one's hometown family and friends retains far more people than "My Hometown" sentimentality.
The Bakkus Shale in ND may seem tempting, if not for the one of the jobs in the gas fields then at least for one of the many support jobs opening up (everything from secretarial, waiter(ess)/bartender, garbage collection, etc. But consider most of the people most needing to get out are the ones with the lowest skill levels, education, and employment strengths. Those people can HARDLY count on getting a good paying gas field job and would at best be looking at a lower skilled (and thus lower paying) job like waiter, food service, etc. Yes, the job demand is out there and wages relatively high compared to (e.g.) Lima, but so are the costs of rent and living in general. So the scenario for most people is to pack and leave and somehow absorb the upfront costs not just of moving/gas, but security deposit and first month's rent that, due to the boom, is likely substantially more expensive than what they pay back in the Midwest (and that's just for the spartan cramped temporary worker housing/trailers put up for newcomers, but we're assuming they're willing to rough it). Again, this assumes a job is readily available even in boomtown once you get there. Odds are currently good, but it's a gamble for folks living (at best) paycheck to paycheck.
That's not an automatically insurmountable hurdle for everyone (though it is for a fair portion of the underclass), but it return they have to give up the economic security of family and friends able and willing to offer/share childcare, an extra bag of groceries the fridge is empty before payday, maybe a little case when the utilities are close to being shut off, even a couch or spare room to stay in if there are troubles with the landlord or finding a new place, not to mention job referrals that might help with employment (temporary, informal under the table, or otherwise).
And that's not including the many folks who are tied to house with an underwater mortgage and see marginally better hope of waiting for better times (and real estate values) rather than default and definitely lose tens of thousands, or who are otherwise tied to family who are infirm/special needs, or otherwise in need of support; family members whom they can't support trailblazing to North Dakota but aren't willing or able to merely abandon into social services.
That's a lot to give up to swallow the not-inconsiderable costs of relocating to a boom area to hunt for a job that will probably be there and probably make up for the increased cost of living, but with questionable reliability beyond the short term and giving up the financial safety net friends and family can provide. I accordingly question how many of these people staying in their rust belt towns are simply stubborn sentimentalists rather than rational economic actors. Certainly both types exist, but I suspect there are more of the latter than people assume.
To add to what Badger said, there's also a micro-macro issue going on here. What's good advice to your 19 year old nephew isn't really a good solution for the region's unemployed as a whole.
