OK, I've changed my mind: the Broncos will win next year. The last time Wayne Bennett didn't coach Origin they won the comp. And it'll be Gordie's last year (I think).
It'd be much better and more fun though if the Warriors won. That would be neat. History, though, dictates that it'll be the Cowboys who are one of the grand final teams, if you consider the Kevin Campion factor:
1996: St George in the GF (featuring Campion)
1998: Brisbane in the GF (featuring Campion)
2000: Brisbane in the GF (featuring Campion)
2002: Warriors in the GF (featuring Campion)
2004: ???