The mouth says one thing and the heart has a plan of it's own before you go floating away make sure that you understand what's behind the curtain of his words. And one thing before I close the door on this question,know that you were beautiful before he said that you was.
It depends on who the guy is. I have a guy friend that says that to me all the time, but it's just his personality to flirt with every girl. He still means what he's saying, but it doesn't mean he has a crush on me. On the other hand, some guys will only say that if they're interested in a relationship. Regardless, it still makes me feel good when a guy says I'm beautiful.