The old adage holds true: no Republican has ever been elected President since the 19th Century without carrying OH. Its a true swing state.
You can be sure if Romney is up in FL, he’s ahead in OH. Obama will win PA next door - too much liberal deadwood in Philadelphia and Pittsburgh for a Republican to carry the Alabama rural counties in between - they don’t have the votes to take a GOP presidential candidate over the top there.
I think you are right about PA, although the big purge of 100,000 mostly from Philly, will make it more interesting. A shift of just 1-2% indies and PA falls.
I think the “enthusiasm gap” might come into play. I think a lot of blacks just won’t bother to vote this year. At least I hope so.