After Twilight is crowned and she turns to see her friends smiling at her, they are on the wrong side of the dais.
At Twilight's coronation, when Cadance is first shown she has her mane in the style Rarity put it in during "Games Ponies Play". When she comes with Shining Armor to greet Twilight, her mane is in its normal style.
Throughout the coronation, the top of Twilight's mane constantly changes back and forth from her curved formal style to her regular straight style.
During Twilight's coronation, Luna has her regular black crown instead of her formal crown in some scenes.