It's a pretty safe bet he'll be with us next year. Has been great at Sandy, and will start getting a shot at AFL level next year I think. With Neitz retiring in a year or two, Newton is the best and most logical replacement long term. Hopefully he will be eased into the team while Neitz is still around, so he can teach him, mentor him, etc.
He'll be staying with us, unless he gets selfish and decides some like the Hawks will give him a game now instead of waiting for a position with us. But that seems highly unlikely IMO.