Your princess has now grown up enough to understand the difference between a doll and a car. Her understanding of her gender is surely going to dominate her choices when it comes to playing. Now she will be more comfortable playing with girls instead of boys and will show more interest in colors, decorations, soft toys, dolls and other girly things.
What you need to know
Just because she is interested more in things belonging to her gender doesn't mean that you will keep her away from activities like playing outside and general sports. Encourage her to participate in school basketball or volleyball team.