Martin Wachs and I take a stab at answering this question in the new issue of the UC Berkeley Planning Journal (PDF here).  Excerpt from my recommendations:

[S]cholars and practitioners need to better link land-use development to transit infrastructure. They should support policies that
require density (or local plans to enable density) around transit stations and corridors. Such requirements at the federal and/or state levels could change the rail and land-use decision-making dynamic for local officials, whom otherwise might be easily influenced by well-resourced constituents at the expense of the regional good. The requirements could also deprive local groups of litigation opportunities to slow, stop, or drive up the costs of rail and related development.

Planners and practitioners should also advocate for nonrail options that can catalyze land-use changes, such as bus-rapid transit systems
on bus-only lanes. These lower-cost transit modes can be as clean, fast, and reliable as rail.  Advocates need to communicate these benefits as an antidote to the negative bus stereotype.