Other mistake: When Magneto is overlooking San Francisco Bay (just before lifting the Golden Gate Bridge), the scene was shot on a green screen, as whoever keyed in the sky cut off the very top of his head. What's more, it shows the characters in profile with the setting sun behind them, but they are not in silhouette. What light source in San Francisco is bright enough to outshine the sun?
Revealing mistake: After Jean kills Charles, Jean's house (which is suspended in the air) crashes downwards. Watch the scene very closely, and you can see some minor slip-ups in the computer rendering that give it away as a CGI shot. For example, some of the debris on the walkway in front of the house vanishes after landing. A very small piece of debris on the walkway is also seen "popping" upwards for no reason after having sat still for several seconds. Also, right before the shot ends, a few piece of debris in front of the middle window on the roof begin to flop about before flipping upwards in defiance of gravity. There are also several other minor issues with the shot. (Jean is no longer using her powers once the house falls, so this can't explain it).
Chosen answer: 1) Apparently the combination of Logan's unbreakable skeleton and healing factor was enough to keep Jean from shredding him - it's possible to see his body getting damaged and repairing itself in a few shots. 2) Because, while he's capable of getting close to her mostly intact, the same isn't really true of anything he might be wearing or holding, so any cure syringe he carried with him would be destroyed. 3) Who knows? Given her extreme power level, the cure might or might not have worked, and, considering the final shot of the movie, which suggests that the cure isn't permanent anyway, her powers would likely return before long.
Tailkinker ★