He's surely done in NZ Rugby Union - I'd be stunned if he hung around more than a year or so. He's got what he wanted (i.e. the ability to brag that he's a World Cup winning All Black) but the truth is, the team proved they didn't really need him. His contribution to the later stages of the tournament was absolutely zero. In the semi and the final he spent more time in the sinbin that he did on the field. (Did he even touch the ball in the final? Maybe once?)
I think his ego, wallet and Nasser will drive him wherever the money is and wherever he'll be blindly loved. Behind Smith and Nonu, he'll never be adored the way he wants to be by the All Blacks. That either means French Rugby Union or maybe, with a bigger TV deal, the highest NRL bidder. I doubt his marketability in NZ is anywhere near as high as he imagined it would be after a World Cup win given his little more than cheerleader involvement in the business end of the comp.