I think today is the day that Dempster returns to form. Although, I think it would be really smart to start Buch today if he can, and then bump everyone back.
Not only does that get Dempster the start in Philly rather than in Boston, where he'd get the pitcher rather than the DH, but it also bumps Lester from Thursday vs PHI to Friday vs NYY, and it lines Buch up for the Sunday night start in NY.