Let's keep in mind that if the Yanks weren't using 75,000 different pitchers for the first two months of the season that they'd probably be 10 up on Boston. The Sox have done absolutely nothing in the last 2 months.
This is true, but it also regression to the mean - players like Cano, Matsui, and Abreu were performing well under their career averages at the beginning of the year. The Yankees had terrible injuries in the beginning of the year as well, throwing out a roation that included Karstens, Rasner, and Igawa coupled with Pettitte and Mussina, with Mussina off to a horrible start.
People are quick to point to the easy part of the schedule, but leading up to it, the Yankees took 3 of 4 from Minny and 2 of 3 from LA. They have an incredibly potent lineup, a solid pitching staff 1-5, a much improved bullpen, and a now great bench.
Even with all that, they could easily miss the playoffs because of the horrible start. The WC could be maddening this year, with a ton of teams in it until the last week.