None of the CDs I have that are also available as Mastered for iTunes were matched to the Mastered for iTunes version. I noticed in the iTunes store that the Mastered for iTunes album release dates were newer and the old non-Mastered for iTunes versions were still available. So... my quick test has the same results as the others here and the answer to the OP (for now) is "no".
I still don't have Match, so I may not understand fully how it works, but have you tried to "rematch" since the albums became MFI or were they already MFI when you created your original match? Or does it even matter, does Match just go out and replace old tracks with MFI material on its own? Sorry for the ignorance on the subject.