Winter vacation to Casablanca concerns?

Although I think Angela overplays the threat of armed robbery, I agree with the rest of her information. Casablanca has that huge modern mosque but otherwise is far less interesting than, say, Fez or Marrakesh or Meknes. And since it's a Muslim country, don't expect much for Christmas. Spain, France, or Italy would be a more high-key place to spend that holiday.

Beggars are highly persistent, and pickpocketing does happen, so watch your bags.

I wouldn't call a trip to Casablanca a safari. Not a whole lot there for tourists unless you want to visit the big mosque. Pickpockets, thieves, razor-wielding strong-arm robbers who will slash your face if you wander into the wrong neighborhoods. I have to wonder why you are going to Morocco for Christmas & New Year's, they don't celebrate either of those publicly, and the weather is liable to be overcast. Spain would be a better choice for celebrations.

Also take care what you eat and do not drink water unless it has been boiled. They are a dirty lot I'm afraid and I know folk who have gone there and suffered bad food poisoning, etc.