I believe it's a matter of personal choice or family tradition in the more moderate Islamic cultures. In my many trips to the Middle East and North Africa, I've seen Islamic women wearing everything from abayas to western dress with and without veil. There are many different interpretations of 'modest' so what may be considered modest by one could be scandalous to another.
very well said Ugly Betty
very good points.
IMO,i don't think we can see Rania in that clothes she wore lately during her holiday in the streets or beaches of Amman,not that i have anything against her look,but seriously i am not seen her in sush clothers in Jordan