I take it those big red and pink groupings are hypothetical?
Along similar lines (though not as expansive as Tysons, and with only one rail stop that's maybe seven years out), the City of Bellevue is looking at Downtown height and FAR options. Great hypothetical renderings included. Potentially a 600' zone vs. the current 450' limit.
http://www.ci.bellevue.wa.us/pdf/PCD...sentation.pptx