I think Letizia looked fabulous! The skirt worked well when viewed in the correct light, I think some of the photographers just caught it in the wrong light and angle to do it much justice. It was a bold and unique look, I think. Love the new tiara, I wish we could see the hair from the back, as it looks lovely from the front and sides. Letizia is becoming one of my favorite royal "dressers" her style is more classic during the day, business like and clean cut, and then at the galas she tries new and exciting looks that most wouldn't try! As always, red is most definitely a good color for her, she wears it well...
As for the push up bra, I think it works well with this particular outfit. I'm not saying she should wear one all the time, but if she didn't wear something, with the skirt the cut that it is, she would have no curves at all.