Well, the only thing that will tell you for sure if it is a boy or a girl is a chromosomal analysis (done through amniocentesis) or - if you're lucky, the baby cooperates and you have an experienced doc - an ultrasound. All the rest are old wifes tales and you can't be sure about it. Even thou they do say that when you are carrying low and to the front rather than the sides, you will have a boy, even thou in europe it's the other way around. They say that to me all the time. I am totally carrying to the front - if you look at me from behind, you can't even see that i'm pregnant. So everybody thinks that I will have a boy. I guess we'll find out in may!
Hope this helps, good luck to you!