Wulllllll......IM got 251 reviews and 17 rotten. Thor is 131 and 5. Soooooo, if Thor gets 90% from here out with 120 more reviews, it would exactly equal IM. If it gets fewer reviews, it would have a slightly higher ratio. If it gets more, it would have a slightly lower ratio.
Anything over 9 out of 10 of the remaining reviews would pretty much ensure an IM percentage or slightly above. Right now it's getting about 25 out of 26, but the last 60 reviews have been about 14 out of 15.
That's a very long winded way of saying "It depends on whether or not the critics who have submitted reviews are representative of those who have yet to submit them." This is a way of saying "As we get more info, we'll have a better idea." This is, in turn, a way of saying "We'll know for sure when the final numbers are in."
Genius, huh?

t:
TBH, I think the odds are pretty good.