I am an italian, born in Sicily, living and working there (but not married to a girl from Sicily...), so here are my views on "how sicilian girls are". I think that there is a great difference between girls living in one of the 3 large towns (Palermo, Catania or Messina, and even Siracusa) and girls living in the countryside or in small towns or villages. The former are (on average) more open-minded, more curious and more eager to know new people, including foreigners. Often they are also quite well educated, go to the University (do not forget that it is public in Italy, and the tuition fees are much lower than in the USA), are on average more cultivated and self-conscious. It is true however what aj_mack writes: they usually have the all family in the same town, so do not expect a great sexual freedom from them!
At the very end, I entirely subscribe what aj_mack writes: once married, they will give very much, but do not think that they could not divorce! They are not anymore used to think that marriage is the most important event in their life. There has been a significant evolution, under this respect. I know many divorced girls/ladies. Note: very few girls would accept to be housewives today, in the 3 large towns. Most of them want a job. Personally, I appreciate this attitude.
In conclusion: I think that girls from Sicily are very, very similar to girls from any other part of Italy. But if you like dark skinned girls, you will easily fall in love, in Sicily!
Good luck