benokobi: Hamilton will go after more money for 2019 and make a stupid decision like Alonso and end up in a awful car and his true colours will show
I'm more inclined to believe that Hamilton won't remain in F1 beyond his current contract.
(If he win's the Driver's championship again this year I'd say there's a "better than even" chance of him retiring - If he wins it in 2017 as well then I'd call it a near certainty.)
Time will tell :-)
I can see him staying if he's in a winning car. Its in their blood. I feel though that he would stop short of staying should the car or his age took the shine off his talent.
As you say, time will tell