VRE plans to extend service west to Haymarket and south to Bealeton in Fauquier County.
The normal response of Northern Virginia residents to such proposals is "Great, we need alternatives to people driving cars on congested highways. Let's get Amtrak to add extra trains as well from Lynchburg, and commuting by train will help solve the traffic problem."
However, another perspective is that we have a land use problem. Extending train service further away from the already-developed area facilitates sprawl deeper into the rural countryside. Making it easier for people to live far away from their jobs might not be a solution, if the problem to be solved is land use rather than transportation.