I go back and forth within myself on this one. Actually, I don't know if I was DF'ed in absentia.
It really depends on if you want a clean break or if you want to make them work for it. Let it go and move on, or string them along...
Since you really have "nothing" to lose, I'd say go for it. Make the clean break, move on with the rest of your lives. Just take some of the advice in that thread that was posted and make sure you cover your ass legally.