When a disaster strikes, good information helps understand the situation, it helps the planning and execution of the relief work needed to bring some normalcy back.
On OpenGeoData there is an article that explains how the Fairfax County Urban Search & Rescue Team uses OSM maps on their Garmin units. It is a happy situation that these maps are there for everyone to use.
When you look at the localisation statistics for OSM, you find that Haitian Creole is missing. There is a Haitian Wikipedia so there is support for this language at translatewiki.net. It would be good if we find people willing to work on the OSM localisation as well; this will make the maps useful to the people of Haiti as they are rebuilding their country.