I totally agree that the importance of geography is only occasionally touched upon, usually when working-from-home topics arise.
But it's crucial.
I know a lot about canvas. I'm the top answer-er on StackOverflow for Canvas and HTML5 tags. By far. I love it, I love helping people. Because of this I get emails weekly from people with various issues and I try to reply to them as best I can. Job offers come in too, from uh, one corner of the globe (a little place called California). I reject all of them out of hand because they reject me out of hand, because I won't move.
It might sound like I'd work somewhere special or prestigious (do they still say that about companies?), but I don't.
I'm a person before I'm a programmer. And I always will be. And I have a family and friends and a home in New Hampshire and I want to stay here, even if that means staying with my teeny tiny less-than-ten-person company. And I probably get paid a pittance of what I might get paid out in CA (chuckles were had when I last mentioned my salary on the phone).
But I walk seven minutes to work every day. And lunches are paid, and I feel relaxed and at home, and at noon I can go home (paid lunches, no clock) and cook eggs and swing by the cafe to find fresh coffee and see the faces Jed and Emily and Sam and Alyssa and all the others that I know and love. Just seeing some of the same people every day, people I've known for years, brings me immense joy.
I'm not curing cancer, but at the end of the day I do feel accomplished and refreshed and loved by coworkers and friends in my tiny little world.
Well. I think I've sort of lost the point I was getting at in my own head. Anyway, suggesting people merely uproot their lives seems like the height of insanity, and while many a brave soul do it, I don't think I ever could, not even for cancer-curin'.
 One company to date has said that not-relocating my entire life is OK with them.