Both teams have had problems with their pitching at points in this season. The Mets are really good, but beatable (the Phillies have played very well against them recently).
The reason why I think the Yankees will win is because even when they don't hit well, they make the other team's pitcher work. The Yankees took a lot of pitches before Abreu arrived. But Abreu works pitchers more than any other hitter in Major League baseball. I think he's going to be scary now that he finally has a chance to be seen in the postseason. Also key Yankees (such as Jeter) and their manager have a lot of experience in the post-season.