This is the second post in a series of blog entries on how to solve Drupal mapping problems with the OpenLayers Module
The OpenLayers module has support for all sorts of different layers - KML, WMS, WFS, Vectors &c. The list goes on. However, currently there is no UI for adding new layers. Eventually there will be, but for the time being we need to rely on modules and code to make new layers available to presets.