Connecting for Wildlife started to earn press in the Spring of 2013. Here are a few examples of the coverage.
http://wamc.org/post/berkshire-volunteers-help-identify-roadkill-hotspots
The following resources serve to answer why, where, and at what cost.
Western Transportation Institute:
http://www.westerntransportationinstitute.org/documents/reports/4W1403_Final_Lit_Review.pdf
Arizona Department of Transportation-
http://ntl.bts.gov/lib/46000/46600/46644/AZ603.pdf
http://www.ttap.colostate.edu/downloads/safety/AZ%20AnimalVehicle%20collisions.pdf
U.S. Department of Transportation
Federal Highway Administration
http://www.fhwa.dot.gov/publications/research/safety/08034/08034.pdf
http://www.fhwa.dot.gov/publications/publicroads/09septoct/03.cfm
International Conference on Ecology and Transportation
http://www.icoet.net/ICOET_2013/index.asp
and check out Connecting for Wildlife in the News!