You know how SAT is arranged in order from easiest questions to most difficult? And how SAT verbal has a few straight-up vocab questions, a few "do you know what this word means in context" questions, and then the rest are "main idea" questions?
I feel like if you take the most difficult/ambiguous questions of that third category, you get the MCAT verbal section.
I got 800 on SAT verbal, and I'm sure I could do it again, but I'm hanging around 10's on MCAT verbal. :/ So despite some overlap, I'd say it's definitely different...