Most of these Amazon techies will probably live in LIC in the towers in the sky and walk to work.
In Seattle, instead of living right next to work in some giant tower, a lot of Amazonians ended up living in nearby neighborhoods with more character and better restaurants and bars, like Capitol Hill and Queen Anne, where they could still walk or cycle to work but where the housing stock was older and nicer.
As Amazon grew, the area directly around their HQ tended to become more boring and sterile, as existing businesses closed down and were replaced with giant new Amazon buildings, which sometimes had a Starbucks or other shop on their ground floor but were basically a dead zone at night and on weekends. By far, the most lively place near Amazon was a Whole Foods, which closed at 9pm and is now part of Amazon anyway.
If Long Island City is really chosen for the HQ, then I would expect a lot of people to live in Astoria, Greenpoint, Sunnyside/Sunnyside Gardens, etc, instead of actually living in Long Island City where everything seems kind of ugly and bland. Maybe Jackson Heights near the Roosevelt/74th station as well, though it is much too far to walk, but the subway access is pretty great. Or maybe the area near Forest Hills station if they have kids and want the best schools, but most Amazonians had dogs instead of kids, so expect to see a lot of fancy dog daycares and salons pop up in Queens
Here's an example of how many buildings Amazon now occupies in Seattle, although even that map is out of date:
http://www.amazonhqtours.com/take-an-audio-tour/. That whole area marked with yellow buildings was dead outside of work hours, and not somewhere most people wanted to live, especially because they often didn't hold positive feelings towards Amazon and didn't plan to stay working at Amazon for longer than 1 or 2 years.