I doubt Kreider can just step in next year and play for the Rangers. I would like to see him score at a 1.5 point per game pace to have hope of him playing for the Rangers in 2011.
WJC is close to the NHL in talent (though obviously much less in experience), but still lower. If you hope to play in the NHL, you should be able to play heads and shoulders above the average WJC player.
Step was the gold standard for that: team captain of a gold metal winner; tournament leader in points; excellent hockey sense and size.
I would say Kreider has the size and the speed, but I want to see him dominate teenagers before he's thrown to play against NHLers.
I want him to get point per game against the top team, and multiple points per game against the bottom-feeders.
If he doesn't do that, it's ok, but it will be a sign that he's not yet NHL-ready, which honestly I don't think he is.