https://maps.google.com/maps?q=Kennedy Square public housing property&oe=utf-8&client=firefox-a&ie=UTF-8&ei=ZajuUoeGIoakyQHYuIHQCw&ved=0CAkQ_AUoAQ
A map, including directions from the current Carrier Dome box office to the edge of the new stadium site. It is less than a mile from the current Carrier Dome. Given enough parking and space for other attractions, it could be a great site. It is fairly cheap too, you can buy a decent sized building for ridiculously low prices, and the area is currently unsafe enough that you wouldn't want your business there. Urban renewal is all part of the reasoning for the location.
I envision something like Fenway Park and Landsdowne St. Those businesses get a tremendous amount of business when there is a game or other event, but are perfectly viable when the Sox aren't in town or in the offseason. Of course, with Football, Basketball, Lacrosse and other events, there hopefully wouldn't be too many periods with no events at all.