He has a flawless butterfly style and plays percentages with the fundamentals of movement that are next to none right now. He keeps his legs wider apart than Patrick Roy and leans forward with a perfect spine angle, so it appears as if he brings his shoulders up and out like he is "hunching" up.
With the guidance of Francois Allaire, his goalie coach, J-S has perfected the "push" with his blades, while on the ice with his other knee. How many times during the playoffs have you seen him move from one side of the crease to the other with just one push, and then make the save with his chest? Just ask the Wild, Stars and Wings about how frustrating that can be. I'm sure the Ducks equipment manager had to sew a new logo on; the old one was probably all black from the puck hitting him.
He also keeps his arms nice and tight to his body, rarely allowing anything to squirt through. The same thing applies to his legs. He leaves his pad straps loose so the pad lays flat on the ice right away when he goes down into the butterfly.
Another strength I have seen is how good he is at analyzing games and situations once they are over. If he makes a spectacular save -- like the one on Mike Modano with his skate -- he says it shouldn't have happened anyway because he was out of position. He is the new wave of premier puck stoppers in the NHL, and his career is just beginning.
The negatives? Have you seen any? I haven't. It may be pucks that are shot from around the bottom of the circles to his stick. I noticed the Stars doing that more, and they had the far wingers driving to the net for the rebound. It is a tough play for any goalie, as it is hard to control the rebound from that angle.
He is not much of a roamer, so he doesn't play many pucks. And that is not his strength, so he stays home a lot more than Brodeur.
Brodeur has an amazing amount of athletic ability; that is why he doesn't show the shooter the same move in similar situations. On one play he will two-pad slide; on another he may use a half butterfly or paddle down. When a shooter is coming down the wing, Marty will often "drag a pad" or "lean" toward the post. I haven't seen a left-handed shooter beat him high to the glove side in a long time; he has great instincts to his glove side and terrific hand-eye coordination to go along with quickness.
Marty has the best "hockey sense" of any goalie in the NHL (Dallas' Marty Turco would be next). He reads the play as it develops and plays the puck better than half the defensemen in the NHL, which helps his defensemen when there are odd-man breaks against or dump-ins to his corners. As soon as the puck gets dumped in, his defensemen or the forwards get to open space so he can pass them the puck. They don't come to him; they get away from him so he can make that pass.
If there are any negatives to the way he plays, it's that he doesn't always make the shooter earn a goal with a perfect shot, like many of the percentage goalies. Pucks have snuck through him, like Radek Bonk's goal in Game 6. There are times when the short side is open because of the way he leans -- an example of this would be Vaclav Varada's goal in Game 4.
Marty's strength remains his mental toughness, his even-keeled demeanor and his big-save mentality. He reminds me a lot of Grant Fuhr when it comes to making big saves. There is always a time in the game when momentum can swing one way or another, and Marty always gives his team a chance to win, no matter what the score is at the time.