Check out [link|http://earth.google.com|Google Earth] too, if you've got access to a recent Windows machine. The pictures are from different archives, in many cases, and are probably updated differently, but at least in the DC area you get sharper images with Earth than with Maps.

The source for many of the satellite pictures used by Google and others is [link|http://digitalglobe.com/katrina_gallery.html|Digital Globe].

Best of luck to your family and friends down there. :-(

Cheers,
Scott.