Sorry to be sexist, but I think boys play sooo differently from girls. I am sitting here in my windowseat watching the puppies (Max and Ben) play. It is completely physical and lightly abusive. They smack at each other, say, "ha-ha!" like
Nelson Muntz, grab at each other's feet and pull one another to the (hard) floor. Usually it is Max who gets Ben, then he kisses him a little! Puppy love. My heart melts at their sweetness. I sit in a love-drunk stupor, a pile of sugary Mommymush.
When I was a girl, my sister and I only rough-housed when we were either truly fighting or playing "fight in the dark" with my boy cousins, Larry and Ronnie, who were our age, a little older. Sometimes other cousins were there. We would go into their parents' bedroom, all get on the bed, shut the light, and who ever you would bump into you would wrestle. Totally innocent, I swear! It was pre-pubescent play. It was just pure fun, and sometimes a little painful, but nothing inappropriate. I remember getting hurt once, and crying to my dad, who said, "Well, you're going to play with the boys, you're going to get hurt sometimes." I heard him, believed him, and went back for more.
As I grew older, I realized that truer words were never spoken, right girls? Yet my enjoyment of playing with boys has never dimmed.