I don't know about Boston, but Maine is not in any sense close to nyc. I think the difference is distance. In sf, world class skiing is 3 hours away; the beach is 20 minutes in much of the city; great hiking is across the bridge in Marin or south along 1, well under an hour away. It's not a trip; enjoying the outdoors takes an afternoon. I have an acquaintance who works near the presidio and surfs over lunch. When I lived in Manhattan, you could definitely get to the outdoors, but it wasn't anything like this close.

As for jobs, I disagree. see eg:

machine learning, nyc: 1 responsive ad (plus ads for jobs in sfbay, nonresponsive android stuff) http://newyork.craigslist.org/search/sof?query=machine+learn...

same search, sf: 10-15? http://sfbay.craigslist.org/search/sof?query=machine+learnin...

indeed has similar ratios.

As for jobs in general, if you're a good js or rails engineer with a reasonable network of friends / former coworkers, starting now at 6pm Tuesday night you could have interviews on Friday, maybe even on Thursday. And start a new job next week. I believe there's a qualitative difference.