A bit after the fact, but still very interesting information. How Openstreetmap has been used to help NGO’s work in Haiti after the earthquake. A specific webpage has been set up for the occasion: http://www.openstreetmap.org.ph/
A thorough article by Camille Gévaudan, in ecrans.fr (in French).
Other informations in opensource.com
Quick selection of images:
Map showing the depth of flooding, using OSM road data.
Port au Prince before and After