I've been watching every Oiler game this season and Mcdavid is an amazing talent that will be the best player in the world eventually.
That said, i don't think he's quite there yet. He's fabulous off the rush and turns nothing plays into scoring chances, but i think Crosby is better at using his linemates to keep the other team pinned in their own zone for long stretches at a time. Mcdavid's half court down low game needs some work, and that will come with strength and maturity.
Crosby was incredible in the world cup, and despite the setback of missing the first 6 games, looks to have picked up where he left off. 5 points in 3 games so far.
I'd also keep an eye out for 2 time art ross winner Malkin. He's looked really good and has 10 points in 9 games himself.