Proactive steps to prevent DDOS?

[Sean Donelan <sean () donelan com>]

Ok, Yahoo, Ebay, Amazon and Microsoft have all made essentially the
same statement after being hit by a DDOS:  "taken steps to
improve protection of their networks from this type of attack."

My question is What are these steps, and why can't people take them
before they experience a DDOS?

Is there some magic command I can put into my router to help protect
my network from a DDOS, or is this just PR fluff to make it look like
the corporation is doing something.  But in reality there is nothing
you can do, but wait for the attacker to get bored and stop on their
own.