I'm not sure a whole lot of people have to bomb....Rachael could easily come in 3rd if Yuna wins first and Miki wins second. Here's why: Rachael knows how to work the CoP. Her scores at SA was 174.91, Mao's score at TEB was 173.99. Mao did not make many mistakes at TEB, she popped her 3a in the short, hit her 3a-2t in the long, 2footed her second 3a in the long (resulting in a downgrade) and fell on her 2a. Rachael fell in the short and her last spin did not count, so she also could have been higher. I highly doubt Mao will land all three of her 3a attempts, if she hadn't gotten the second one in the LP downgraded, her score would be about 5 points higher, so that gets her to 178. If Rachael's spin had counted, she'd be about 5 points higher as well, getting her to 179.
Rachael can edge out a Mao with 2 3axels if she hits all her jumps, which normally she does, and fixes her last spin. If Mao hits all three of her 3axels, she will probably be in 2nd behind Yuna (even if Yuna makes some mistakes). But how likely is Mao landing all three of her 3axels? Not very. It usually seems that she pops one, lands one, and has one UR. If that happens, Joannie, Miki, and even Rachael could bump her out of the running, all they have to do is skate clean. They are smart though and realize you don't have to take huge risks to rack up points.
I leave out an spoilers, such as Carolina, who could medal if she skates clean and hits her 3-3. Alissa I think has only a very slim shot at medaling as her FS is not technically up to par with the top girls. I suppose if another European does all her triples the judges could get really excited and let whoever that may be medal

. At this point I put Miki ahead of Mao, and Mao and Joannie equal (both have potential but have had problems recently), but Rachael is right behind them