I lived in Boston (Inman Sq, Cambridge, later Back Bay, Boston) for 5 years after my undergraduate education. NYC is far, far more interesting and exciting than Boston. As an indirect indicator, NYC draws far more VC than Boston.
More importantly, Boston is much heavier into manufacturing technology, hardware, B2B software, etc whereas NYC is more focused on consumer, retail, fashion, etc. Boston is pretty clearly a better choice for GE.
Given that GE is its own VC for the context, they really don't need to be in NYC.
More importantly, industrial Internet of Shit developers, smart grid companies, and related activities are going on at the Seaport District, right where GE is setting up shop.