With Moro it depends on who's at the door... with men she knows and likes, she'll usually wag her tail a lot and roll over wanting a belly rub... with women she knows (including me), she'll jump up and try to lick and cuddle. She always jumps up when I get home from work every day.
If it's a man she doesn't know, she'll growl and keep her distance until we 'introduce' her....she also doesn't like strange men walking through the house and will growl if they try to go through our bedroom (you have to walk through our bedroom to get to the bathroom in our house). She has never bitten anyone but she is very protective and wary of male strangers.
With female strangers, she's a little more relaxed...she'll usually wag her tail and slowly approach, and will become a total goofball if she decides that this is someone who likes her and is gong to give her attention. It's a little easier to get her to trust women she hasn't met before than men, for some reason, but she will generally accept anyone after spending a little time around her.
Now Midas, he wags his tail and jumps up for me, my husband and our roommate...anyone else, he doesn't really do much. He isn't that interested in meeting strangers, and truthfully he seems scared to meet anyone he doesn't already know. He is also protective of the bedroom and will bark if someone comes to the door while we're in the bedroom.