Has there been any indication of the new HQ's purpose? Duplicate functionality, admin, technical, etc.?
I've wondered why they wouldn't simply locate the new HQ at or near their existing NoVa location(s).
If I'm (not) betting, I'd flip the Dublin bookmaker's DC-area rankings: NoVa would seemingly have the things that people "want" (traffic and all), while Maryland wouldn't seem to resonate, and DC seems better suited for a small footprint/satellite office (lawyers and lobbyists).