It seems to me that Jack didn't roll on anyone significant. If he had, he would have gotten a lighter sentence. The maximum he could have gotten was 7 years and this is pretty close to the max. I know this isn't a sentence for the main case against him but I'm sure that prosecuters talk to each other and make deals across jurisdictional lines. The Feds could have told the FL prosecution to lighten up if they were getting anything interesting or useful from Jack.
I think we can probably give up any hope of some real juicy indictments coming out of Abramoff's disclosures. It seems that he is keeping his mouth shut. Besides, Bush will pardon him, anyway.