Per Brit Hume interviewee today:
In Wilson's book the states that both he and Plame came back to the U.S. in 1997. The way the applicable law is written, you have to be on a foreign assignment within the last 5 years or there is no crime. 2003-1997 is six years so no indictment is possible for the "outing" of Plame.
Unless you are a republican.