Jeff Jarvis of Buzzmachine has a post up called Recovery 2.0: A call to convene, that discusses ways to make the Internet a much better tool to help communities recover from disasters like hurricane Katrina.
It is unquestionably worth a read.
My one criticism, and it's a mild one, is that in Katrina's case, many of those most adversely affected don't appear to be that wired or computer-literate.
That doesn't argue against the initiative; it just means you might need trained volunteers without strong computer/Internet skills to help those in need make use of the Internet's capabilities.