As a completely biased Yankee fan, I'd say this is in-accurate.
One thing to remember is the mid season deals, which the Yankees have never shied away from. They'll get what they need to make it a tight race regardless.
So, even if the Yankees sign Brown or Perez or Sheffield or Guerrero, whatever the roster is as of April 1, you can guarantee it will look different come September 1.
Likewise, if you do a player by player comparison of Yanks vs. Sox, there is no way you can say this is a slam dunk.
Yanks pitching staff is still solid, with two definite studs in Vazquez and Mussina. Contreras still may become the man if he can work on his control a little. He definitely has a devastating splitter, so there's much potential.
I still give the Yanks bullpen the advantage, now that they have Tom Gordon. Rivera and Gordon is a nice combo.
Let's assume Sox trade Nomar and Manny and get Arod:
Second: Yanks by far
Short: Sox by far
Right: Yanks (whether it's sheff or vlad)
This is far from a no-brainer. As people have said about the Braves for so long, until someone beats the Yanks, you gotta bet on them. For the Braves, it's time to stop the betting, but the Yankees are still tops in the East until proven otherwise, IMO.